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Fonseca PAS, Suárez-Vega A, Arranz JJ, Gutiérrez-Gil B. Integration of selective sweeps across the sheep genome: understanding the relationship between production and adaptation traits. Genet Sel Evol 2024; 56:40. [PMID: 38773423 PMCID: PMC11106937 DOI: 10.1186/s12711-024-00910-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 05/07/2024] [Indexed: 05/23/2024] Open
Abstract
BACKGROUND Livestock populations are under constant selective pressure for higher productivity levels for different selective purposes. This pressure results in the selection of animals with unique adaptive and production traits. The study of genomic regions associated with these unique characteristics has the potential to improve biological knowledge regarding the adaptive process and how it is connected to production levels and resilience, which is the ability of an animal to adapt to stress or an imbalance in homeostasis. Sheep is a species that has been subjected to several natural and artificial selective pressures during its history, resulting in a highly specialized species for production and adaptation to challenging environments. Here, the data from multiple studies that aim at mapping selective sweeps across the sheep genome associated with production and adaptation traits were integrated to identify confirmed selective sweeps (CSS). RESULTS In total, 37 studies were used to identify 518 CSS across the sheep genome, which were classified as production (147 prodCSS) and adaptation (219 adapCSS) CSS based on the frequency of each type of associated study. The genes within the CSS were associated with relevant biological processes for adaptation and production. For example, for adapCSS, the associated genes were related to the control of seasonality, circadian rhythm, and thermoregulation. On the other hand, genes associated with prodCSS were related to the control of feeding behaviour, reproduction, and cellular differentiation. In addition, genes harbouring both prodCSS and adapCSS showed an interesting association with lipid metabolism, suggesting a potential role of this process in the regulation of pleiotropic effects between these classes of traits. CONCLUSIONS The findings of this study contribute to a deeper understanding of the genetic link between productivity and adaptability in sheep breeds. This information may provide insights into the genetic mechanisms that underlie undesirable genetic correlations between these two groups of traits and pave the way for a better understanding of resilience as a positive ability to respond to environmental stressors, where the negative effects on production level are minimized.
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Affiliation(s)
- Pablo A S Fonseca
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, Campus de Vegazana S/N, 24071, León, Spain
| | - Aroa Suárez-Vega
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, Campus de Vegazana S/N, 24071, León, Spain
| | - Juan J Arranz
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, Campus de Vegazana S/N, 24071, León, Spain
| | - Beatriz Gutiérrez-Gil
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León, Campus de Vegazana S/N, 24071, León, Spain.
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Zhong H, Ren B, Lou C, Zhou Y, Luo Y, Xiao J. Nonadditive and allele-specific expression of ghrelin in hybrid tilapia. Front Endocrinol (Lausanne) 2023; 14:1292730. [PMID: 38152137 PMCID: PMC10751329 DOI: 10.3389/fendo.2023.1292730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/07/2023] [Indexed: 12/29/2023] Open
Abstract
Background Interspecies hybridization is an important breeding method to generate fishes with heterosis in aquaculture. Using this method, hybrid Nile tilapia (Oreochromis niloticus, ♀) × blue tilapia (Oreochromis aureus, ♂) has been produced and widely farmed due to its growth and appetite superiorities. However, the genetic mechanism of these advanced traits is still not well understood. Ghrelin is a crucial gene that regulates growth and appetite in fishes. In the present study, we focused on the expression characteristics and its regulation of ghrelin in the hybrid. Results The tissue distribution analysis showed that ghrelin was predominantly expressed in the stomach in the hybrid. Ghrelin was more highly expressed in the stomach in the hybrid and Nile tilapia, compared to blue tilapia, showing a nonadditive pattern. Two single-nucleotide polymorphism (SNP) sites were identified including T/C and C/G from the second exon in the ghrelin gene from Nile tilapia and blue tilapia. By pyrosequencing based on the SNP sites, the allele-specific expression (ASE) of ghrelin in the hybrid was assayed. The result indicated that ghrelin in the hybrid showed higher maternal allelic transcript ratios. Fasting significantly increased ghrelin overall expression at 4, 8, 12, 24, and 48 h. In addition, higher maternal allelic transcript ratios were not changed in the fasting hybrids at 48 h. The cis and trans effects were determined by evaluating the overall expression and ASE values in the hybrid. The expression of ghrelin was mediated by compensating cis and trans effects in hybrid. Conclusion In summary, the present lines of evidence showed the nonadditive expression of ghrelin in the hybrid tilapia and its regulation by subgenomes, offering new insight into gene expression characteristics in hybrids.
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Affiliation(s)
- Huan Zhong
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Bingxin Ren
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Chenyi Lou
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Yi Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Yongju Luo
- Tilapia Genetics and Breeding Center, Guangxi Academy of Fishery Sciences, Nanning, China
| | - Jun Xiao
- Tilapia Genetics and Breeding Center, Guangxi Academy of Fishery Sciences, Nanning, China
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Najafi R, Heidarianpour A, Shokri E, Shokri B. Ameliorative effects of aerobic training in girls with precocious puberty: role of leptin and ghrelin. Sci Rep 2023; 13:15732. [PMID: 37735188 PMCID: PMC10575917 DOI: 10.1038/s41598-023-42828-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 09/15/2023] [Indexed: 09/23/2023] Open
Abstract
This study was an attempt to examine the changes in serum levels of ghrelin and leptin after 12-weeks of aerobic training and gonadotropin releasing hormone agonist (GnRH) treatment in girls with central precocious puberty. Thirty girls (6-8 years old) with precocious puberty who had received Triptorelin were randomly divided in two groups (medication and medication + training). Fifteen age-matched healthy girls (without precocious puberty) were also included as the control group. The medication + training group submitted an aerobic training program for 3 days/week with 20-75 min per day and 45-75% of maximum heart rate for 12-weeks. Serum levels of leptin, ghrelin, cholesterol, triglycerides and body mass index (BMI) were determined at baseline and 48 h after the last training session. The results indicated that leptin significantly decreased (p = 0.001) and ghrelin significantly increased (p = 0.001) in the medication + training group but no significant difference was observed in the ghrelin (p = 1) and leptin (p = 0.78) in the medication group. Leptin to ghrelin ratio indicated a decrease in medicine + training group (p = 0.028). Ghrelin were negatively correlated with leptin and BMI. The data indicated that aerobic training increased ghrelin and reduced leptin and leptin to ghrelin ratio but GnRH agonist treatment had no effect on plasma leptin and ghrelin levels.
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Affiliation(s)
- Ramyar Najafi
- Faculty of Sport Sciences, Bu-Ali Sina University, Hamedan, Iran
| | | | - Elnaz Shokri
- Faculty of Sport Sciences, Bu-Ali Sina University, Hamedan, Iran
| | - Behnaz Shokri
- Faculty of Sport Sciences, Bu-Ali Sina University, Hamedan, Iran
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Belén Poretti M, Bianconi S, Luque E, Martini AC, Vincenti L, Cantarelli V, Torres P, Ponzio M, Schiöth HB, Carlini VP. Role of the hypothalamus in ghrelin effects on reproduction: sperm function and sexual behavior in male mice. Reproduction 2023; 165:123-134. [PMID: 36322468 DOI: 10.1530/rep-22-0098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 11/02/2022] [Indexed: 11/07/2022]
Abstract
In brief Ghrelin signals to the hypothalamus inhibit reproduction during times of food scarcity. In this study, we demonstrate that ghrelin impairs sperm quality in male mice. Abstract Ghrelin (GHRL) is an orexigenic peptide that has been investigated as one of the signals responsible for the reproductive performance of mammals under fluctuating metabolic conditions. Central GHRL administration impairs spermatogenesis in mice by regulating the hypothalamic-pituitary-gonadal axis function. In the present study, the hypothalamus role as a mediator of GHRL effects on sperm fertilizing capacity and male sexual behavior was evaluated. After 42 days of hypothalamic GHRL infusion or artificial cerebrospinal fluid, in vitro and in vivo sperm fertilizing capacity, testicular α-tubulin, speriolin gene expression and spermatic α-tubulin protein were evaluated. Hypothalamic expression of genes Kiss1, Gpr54 and Gnrh was also studied. The second group of animals was infused with one time only GHRL or artificial cerebrospinal fluid into the hypothalamus to evaluate the effects on sexual behavior. Results demonstrated that chronic GHRL administration to male mice significantly increased the percentages of pre-implantation embryo loss and the number of post-implantation embryo loss. In relation to the gene expression, our results show a relative decrease of Kiss1, Gpr54 and Spatc1. Although no significant differences were observed in the quantitative expression of α-tubulin protein, qualitative changes in its expression pattern were observed. In addition, a dual effect on sexual behavior was observed: 40% of the treated animals showed a significant reduction in the number of mounts and intromissions, while a 60% showed a significant decrease in ejaculation latency vs control animals. In conclusion, our results provide evidence that central GHRL administration possibly induces failure in embryo development and/or implantation in the females mated with treated males, possibly because of a negative effect in the α-tubulin pattern.
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Affiliation(s)
- María Belén Poretti
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina.,Functional Pharmacology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Santiago Bianconi
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina.,Functional Pharmacology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Eugenia Luque
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Ana Carolina Martini
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Laura Vincenti
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Veronica Cantarelli
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Pedro Torres
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Marina Ponzio
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina
| | - Helgi B Schiöth
- Functional Pharmacology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Valeria Paola Carlini
- Instituto de Investigaciones en Ciencias de la Salud (INICSA, CONICET- UNC), CONICET and Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, Argentina.,Functional Pharmacology, Department of Neuroscience, Uppsala University, Uppsala, Sweden
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Ibrahim I, Syamala S, Ayariga JA, Xu J, Robertson BK, Meenakshisundaram S, Ajayi OS. Modulatory Effect of Gut Microbiota on the Gut-Brain, Gut-Bone Axes, and the Impact of Cannabinoids. Metabolites 2022; 12:1247. [PMID: 36557285 PMCID: PMC9781427 DOI: 10.3390/metabo12121247] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/30/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
The gut microbiome is a collection of microorganisms and parasites in the gastrointestinal tract. Many factors can affect this community's composition, such as age, sex, diet, medications, and environmental triggers. The relationship between the human host and the gut microbiota is crucial for the organism's survival and development, whereas the disruption of this relationship can lead to various inflammatory diseases. Cannabidiol (CBD) and tetrahydrocannabinol (THC) are used to treat muscle spasticity associated with multiple sclerosis. It is now clear that these compounds also benefit patients with neuroinflammation. CBD and THC are used in the treatment of inflammation. The gut is a significant source of nutrients, including vitamins B and K, which are gut microbiota products. While these vitamins play a crucial role in brain and bone development and function, the influence of gut microbiota on the gut-brain and gut-bone axes extends further and continues to receive increasing scientific scrutiny. The gut microbiota has been demonstrated to be vital for optimal brain functions and stress suppression. Additionally, several studies have revealed the role of gut microbiota in developing and maintaining skeletal integrity and bone mineral density. It can also influence the development and maintenance of bone matrix. The presence of the gut microbiota can influence the actions of specific T regulatory cells, which can lead to the development of bone formation and proliferation. In addition, its metabolites can prevent bone loss. The gut microbiota can help maintain the bone's equilibrium and prevent the development of metabolic diseases, such as osteoporosis. In this review, the dual functions gut microbiota plays in regulating the gut-bone axis and gut-brain axis and the impact of CBD on these roles are discussed.
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Affiliation(s)
- Iddrisu Ibrahim
- The Microbiology Program, Department of Biological Sciences, College of Science, Technology, Engineering, and Mathematics (C-STEM), Alabama State University, Montgomery, AL 36104, USA
| | - Soumyakrishnan Syamala
- Departments of Medicine, SUNY Downstate Health Sciences University, Brooklyn, NY 11203, USA
| | - Joseph Atia Ayariga
- The Industrial Hemp Program, College of Science, Technology, Engineering, and Mathematics (C-STEM), Alabama State University, Montgomery, AL 36104, USA
| | - Junhuan Xu
- The Industrial Hemp Program, College of Science, Technology, Engineering, and Mathematics (C-STEM), Alabama State University, Montgomery, AL 36104, USA
| | - Boakai K. Robertson
- The Microbiology Program, Department of Biological Sciences, College of Science, Technology, Engineering, and Mathematics (C-STEM), Alabama State University, Montgomery, AL 36104, USA
| | - Sreepriya Meenakshisundaram
- Department of Microbiology and Biotechnology, JB Campus, Bangalore University, Bangalore 560 056, Karnataka, India
| | - Olufemi S. Ajayi
- The Industrial Hemp Program, College of Science, Technology, Engineering, and Mathematics (C-STEM), Alabama State University, Montgomery, AL 36104, USA
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Chen Y, Li Q, Li X, Liu H, Li P, Hai R, Guo Y, Wang S, Wang K, Du C. Amylin regulates testosterone levels via steroidogenesis-related enzymes in the central nervous system of male mice. Neuropeptides 2022; 96:102288. [PMID: 36279616 DOI: 10.1016/j.npep.2022.102288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 10/14/2022]
Abstract
Amylin is a peripheral satiation signal polypeptide co-secreted with insulin by pancreatic β-cells in response to nutrient ingestion. Amylin participates in the eating-inhibitory effect and regulates energy metabolism by acting on the central nervous system (CNS). However, the role of amylin in regulating the biosynthesis of steroid hormones, such as testosterone, through the hypothalamic-pituitary-gonadal axis (HPG) remains unexplored. However, only limited evidence is available on the involvement of amylin in steroid synthesis, we hypothesize that amylin regulates testosterone levels via steroidogenesis-related enzymes in the CNS. In this study, we elucidated the effect of intraperitoneal injection of amylin on the protein expression of steroidogenesis-related enzymes, including 3β-hydroxysteroid dehydrogenase (3β-HSD), cytochrome P450 17A1 (CYP17A1), and steroidogenic acute regulatory protein (StAR), and phospho-extracellular signal-regulated kinase (pERK). Additionally, the effect of amylin on testosterone levels in male mice was examined. Our results suggested that 3β-HSD and CYP17A1 neurons were widely expressed in the CNS of male mice, whereas StAR neurons were mainly expressed in the zona incerta (ZI) and locus coeruleus (LC) regions. Intraperitoneal injection of amylin significantly reduced (p < 0.01) the expression of 3β-HSD, CYP17A1, and StAR in ZI and other areas near the third ventricle (3 V) but increased (p < 0.01) pERK expression, brain testosterone levels, serum FSH, serum LH, and decreased (p < 0.01) serum testosterone levels in mice. In conclusion, amylin regulates testosterone levels via steroidogenesis-related enzymes in the central nervous system of male mice.
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Affiliation(s)
- Yujie Chen
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China
| | - Qiang Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Xiaojing Li
- College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Haodong Liu
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Penghui Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China
| | - Rihan Hai
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China
| | - Yongqing Guo
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China
| | - Siwei Wang
- Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang 050000, China; Key Laboratory of Crop Cultivation Physiology and Green Production in Hebei Province, Shijiazhuang 050000, China
| | - Kun Wang
- Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang 050000, China; Key Laboratory of Crop Cultivation Physiology and Green Production in Hebei Province, Shijiazhuang 050000, China
| | - Chenguang Du
- Vocational and Technical College, Inner Mongolia Agricultural University, Baotou 014109, China; College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot 010018, China.
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Almasi N, Zengin HY, Koç N, Uçakturk SA, İskender Mazman D, Heidarzadeh Rad N, Fisunoglu M. Leptin, ghrelin, nesfatin-1, and orexin-A plasma levels in girls with premature thelarche. J Endocrinol Invest 2022; 45:2097-2103. [PMID: 35764868 DOI: 10.1007/s40618-022-01841-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/10/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE Reducing the mean age of puberty onset in recent years has crucial public health, clinical, and social implications. This study aimed to evaluate the serum levels of appetite-related peptides (leptin, ghrelin, nesfatin-1, and orexin-A) and anthropometric data in girls with premature thelarche (PT). METHODS We enrolled 44 girls aged 4-8 years diagnosed with PT and 33 age-matched healthy girls as controls. The demographic data of the girls were obtained using a questionnaire. Anthropometric data were measured and fasting blood samples were collected. RESULTS Body weight, height, body mass index (BMI), body fat mass, and basal metabolic rate (BMR) were higher in the PT group than in the control group (p < 0.05). Serum leptin (p < 0.001), nesfatin-1 (p = 0.001), and orxein-A (p < 0.001) levels were significantly higher in the PT group than in healthy controls. However, there were no significant differences in the serum ghrelin levels between the groups (p > 0.05). The results of multivariate logistic regression revealed that serum leptin level (OR (95% CI): 42.0 (10.91, 173.06), p < 0.001), orexin-A (OR (95% CI): 1.14 (1.04, 1.24), p = 0.006), and BMI for age z-score (OR (95% CI): 6.97 (1.47, 33.4), p = 0.014) elevated the risk of incidence of PT at 4-8 girls. CONCLUSION These results suggest that in addition to serum leptin levels, serum orexin-A and nesaftin-1 can take part in the initiation of PT. Few studies have investigated the relationship between nesfatin-1 and orexin-A levels and age at onset of puberty; hence, it should be a subject for future studies.
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Affiliation(s)
- N Almasi
- Department of Nutrition and Dietetics, Hacettepe University Faculty of Health Sciences, Ankara, Turkey
| | - H Y Zengin
- Department of Biostatistics, Hacettepe University Faculty of Health Sciences, Ankara, Turkey
| | - N Koç
- Department of Child Endocrinology, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - S A Uçakturk
- Department of Child Endocrinology, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - D İskender Mazman
- Department of Child Pediatric, Ministry of Health Ankara City Hospital, Ankara, Turkey
| | - N Heidarzadeh Rad
- Department of Nutrition and Dietetics, Hacettepe University Faculty of Health Sciences, Ankara, Turkey
| | - M Fisunoglu
- Department of Nutrition and Dietetics, Hacettepe University Faculty of Health Sciences, Ankara, Turkey.
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Differential Regulation of Gonadotropins as Revealed by Transcriptomes of Distinct LH and FSH Cells of Fish Pituitary. Int J Mol Sci 2021; 22:ijms22126478. [PMID: 34204216 PMCID: PMC8234412 DOI: 10.3390/ijms22126478] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/02/2021] [Accepted: 06/10/2021] [Indexed: 02/08/2023] Open
Abstract
From mammals to fish, reproduction is driven by luteinizing hormone (LH) and follicle-stimulating hormone (FSH) temporally secreted from the pituitary gland. Teleost fish are an excellent model for addressing the unique regulation and function of each gonadotropin cell since, unlike mammals, they synthesize and secrete LH and FSH from distinct cells. Only very distant vertebrate classes (such as fish and birds) demonstrate the mono-hormonal strategy, suggesting a potential convergent evolution. Cell-specific transcriptome analysis of double-labeled transgenic tilapia expressing GFP and RFP in LH or FSH cells, respectively, yielded genes specifically enriched in each cell type, revealing differences in hormone regulation, receptor expression, cell signaling, and electrical properties. Each cell type expresses a unique GPCR signature that reveals the direct regulation of metabolic and homeostatic hormones. Comparing these novel transcriptomes to that of rat gonadotrophs revealed conserved genes that might specifically contribute to each gonadotropin activity in mammals, suggesting conserved mechanisms controlling the differential regulation of gonadotropins in vertebrates.
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Torres PJ, Luque EM, Di Giorgio NP, Ramírez ND, Ponzio MF, Cantarelli V, Carlini VP, Lux-Lantos V, Martini AC. Fetal Programming Effects of a Mild Food Restriction During Pregnancy in Mice: How Does It Compare to Intragestational Ghrelin Administration? Reprod Sci 2021; 28:3547-3561. [PMID: 33856666 DOI: 10.1007/s43032-021-00574-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 04/02/2021] [Indexed: 12/19/2022]
Abstract
To explore in mice if a 15% food restriction protocol during pregnancy programs the offspring postnatal development, with emphasis on reproductive function, and to assess if ghrelin (Ghrl) administration to mouse dams exerts effects that mimic those obtained under mild caloric restriction. Mice were 15% food-restricted, injected with 4 nmol/animal/day of Ghrl, or injected with the vehicle (control) thorough pregnancy. After birth, the pups did not receive further treatment. Pups born from food-restricted dams (FR pups) were lighter than Ghrl pups at birth, but reached normal weight at adulthood. Ghrl pups were heavier at birth and gained more weight than control pups (C pups). This effect was not associated with plasma IGF-1. FR pups showed a delay in pinna detachment and eye opening, while an advance was observed in Ghrl pups. FR pups showed also impairment in the surface-righting reflex. In both female FR and Ghrl pups, there was an advance in vaginal opening and, in adulthood, FR pups showed a significant decrease in their own litter size and plasma progesterone, and an increase in embryo loss. A delay in testicular descent was evident in male Ghrl pups. Changes in puberty onset were not associated with differences in the expression of Kiss1 in hypothalamic nuclei. Finally, in adulthood, FR pups showed a significant decrease in sperm quality. In conclusion, a mild food restriction thorough gestation exerted programming effects on the offspring, affecting also their reproductive function in adulthood. These effects were not similar to those of intragestational Ghrl administration.
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Affiliation(s)
- Pedro Javier Torres
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Eugenia Mercedes Luque
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Noelia Paula Di Giorgio
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental, (IBYME; CONICET), Vuelta de Obligado 2490, Buenos Aires, C1428ADN, Argentina
| | - Nicolás David Ramírez
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Marina Flavia Ponzio
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Verónica Cantarelli
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Valeria Paola Carlini
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina
| | - Victoria Lux-Lantos
- Laboratorio de Neuroendocrinología, Instituto de Biología y Medicina Experimental, (IBYME; CONICET), Vuelta de Obligado 2490, Buenos Aires, C1428ADN, Argentina
| | - Ana Carolina Martini
- Instituto de Fisiología, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, e Instituto de Investigaciones en Ciencias de la Salud (INICSA; CONICET-UNC), Santa Rosa 1085, X5000ESU, Córdoba, Argentina.
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Bédécarrats GY, Hanlon C, Tsutsui K. Gonadotropin Inhibitory Hormone and Its Receptor: Potential Key to the Integration and Coordination of Metabolic Status and Reproduction. Front Endocrinol (Lausanne) 2021; 12:781543. [PMID: 35095760 PMCID: PMC8792613 DOI: 10.3389/fendo.2021.781543] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/02/2021] [Indexed: 12/18/2022] Open
Abstract
Since its discovery as a novel gonadotropin inhibitory peptide in 2000, the central and peripheral roles played by gonadotropin-inhibiting hormone (GnIH) have been significantly expanded. This is highlighted by the wide distribution of its receptor (GnIH-R) within the brain and throughout multiple peripheral organs and tissues. Furthermore, as GnIH is part of the wider RF-amide peptides family, many orthologues have been characterized across vertebrate species, and due to the promiscuity between ligands and receptors within this family, confusion over the nomenclature and function has arisen. In this review, we intend to first clarify the nomenclature, prevalence, and distribution of the GnIH-Rs, and by reviewing specific localization and ligand availability, we propose an integrative role for GnIH in the coordination of reproductive and metabolic processes. Specifically, we propose that GnIH participates in the central regulation of feed intake while modulating the impact of thyroid hormones and the stress axis to allow active reproduction to proceed depending on the availability of resources. Furthermore, beyond the central nervous system, we also propose a peripheral role for GnIH in the control of glucose and lipid metabolism at the level of the liver, pancreas, and adipose tissue. Taken together, evidence from the literature strongly suggests that, in fact, the inhibitory effect of GnIH on the reproductive axis is based on the integration of environmental cues and internal metabolic status.
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Affiliation(s)
- Grégoy Y. Bédécarrats
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
- *Correspondence: Grégoy Y. Bédécarrats,
| | - Charlene Hanlon
- Department of Animal Biosciences, University of Guelph, Guelph, ON, Canada
| | - Kazuyoshi Tsutsui
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Japan
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11
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Pan D, Wang K, Cao G, Fan K, Liu H, Li P, Li H, Chenguang D. Inhibitory effect of central ghrelin on steroid synthesis affecting reproductive health in female mice. J Steroid Biochem Mol Biol 2020; 204:105750. [PMID: 32920127 DOI: 10.1016/j.jsbmb.2020.105750] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 08/17/2020] [Accepted: 08/26/2020] [Indexed: 12/28/2022]
Abstract
Ghrelin is a 28-amino acid peptide hormone that regulates ovarian steroid hormone synthesis; however, there is limited evidence regarding the regulation of this pathway by ghrelin in mice ovary. Thus, we aimed to investigate whether central ghrelin action plays a role in murine reproductive health by inhibiting steroid synthesis. Further, we sought to examine the mechanism of central ghrelin action in ovarian steroid hormone synthesis. After the administration of intracerebroventricular ghrelin (1 nmol), we found reduced serum concentrations of oestradiol and progesterone and reduced secretion of follicle-stimulating hormone and luteinising hormone. Although ghrelin reduced 3β-hydroxysteroid dehydrogenase mRNA and protein levels in the hypothalamus, it did not affect the expression of steroidogenic acute regulatory protein and cytochrome P450 17A1. In the ovary, central ghrelin regulation indirectly inhibited the mRNA and protein levels of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase. Moreover, no changes were observed in the expression of proliferating cell nuclear antigen and phosphorylation of extracellular signal-regulated kinase. We hypothesised that central ghrelin regulation suppressed serum oestradiol and progesterone levels by indirectly inhibiting the expression of steroidogenic acute regulatory protein, cytochrome P450 17A1, and 3β-hydroxysteroid dehydrogenase in the ovary. In this regulation, the suppressed secretion of the follicle-stimulating hormone and luteinising hormone in the pituitary by ghrelin could be involved. Furthermore, hypothalamic 3β-hydroxysteroid dehydrogenase expression is reduced by ghrelin injection.
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Affiliation(s)
- Deng Pan
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Kun Wang
- Institute of Grain and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, 050000, China
| | - Guifang Cao
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Kuikui Fan
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Haodong Liu
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Penghui Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Haijun Li
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China
| | - Du Chenguang
- College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, 010018, China; Inner Mongolia Key Laboratory of Basic Veterinary Science, Hohhot, 010018, China; Vocational and Technical College, Inner Mongolia Agricultural University, Baotou, 014109, China.
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12
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Hill JW, Elias CF. Neuroanatomical Framework of the Metabolic Control of Reproduction. Physiol Rev 2019; 98:2349-2380. [PMID: 30109817 DOI: 10.1152/physrev.00033.2017] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A minimum amount of energy is required for basic physiological processes, such as protein biosynthesis, thermoregulation, locomotion, cardiovascular function, and digestion. However, for reproductive function and survival of the species, extra energy stores are necessary. Production of sex hormones and gametes, pubertal development, pregnancy, lactation, and parental care all require energy reserves. Thus the physiological systems that control energy homeostasis and reproductive function coevolved in mammals to support both individual health and species subsistence. In this review, we aim to gather scientific knowledge produced by laboratories around the world on the role of the brain in integrating metabolism and reproduction. We describe essential neuronal networks, highlighting key nodes and potential downstream targets. Novel animal models and genetic tools have produced substantial advances, but critical gaps remain. In times of soaring worldwide obesity and metabolic dysfunction, understanding the mechanisms by which metabolic stress alters reproductive physiology has become crucial for human health.
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Affiliation(s)
- Jennifer W Hill
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
| | - Carol F Elias
- Center for Diabetes and Endocrine Research, Departments of Physiology and Pharmacology and of Obstetrics and Gynecology, University of Toledo College of Medicine , Toledo, Ohio ; and Departments of Molecular and Integrative Physiology and of Obstetrics and Gynecology, University of Michigan , Ann Arbor, Michigan
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13
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Uenoyama Y, Inoue N, Nakamura S, Tsukamura H. Central Mechanism Controlling Pubertal Onset in Mammals: A Triggering Role of Kisspeptin. Front Endocrinol (Lausanne) 2019; 10:312. [PMID: 31164866 PMCID: PMC6536648 DOI: 10.3389/fendo.2019.00312] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/30/2019] [Indexed: 01/29/2023] Open
Abstract
Pubertal onset is thought to be timed by an increase in pulsatile gonadotropin-releasing hormone (GnRH)/gonadotropin secretion in mammals. The underlying mechanism of pubertal onset in mammals is still an open question. Evidence accumulated in the last 15 years suggests that kisspeptin/neurokinin B/dynorphin A (KNDy) neurons in the hypothalamic arcuate nucleus play a key role in pubertal onset by triggering pulsatile GnRH/gonadotropin secretin in mammals. Specifically, KNDy neurons are now considered a part of GnRH pulse generator, in which neurokinin B facilitates and dynorphin A inhibits, the synchronized discharge of KNDy neurons in autocrine and/or paracrine manners. Kisspeptin serves as a potent secretagogue of GnRH secretion and thus its release is fundamental to pubertal increase in GnRH/gonadotropin secretion in mammals. Proposed mechanisms inhibiting Kiss1 (kisspeptin gene) expression during childhood to juvenile varies from species to species: we envisage that negative feedback action of estrogen plays a key role in the inhibition of Kiss1 expression in KNDy neurons in rodents and sheep, whereas estrogen-independent inhibition of kisspeptin secretion by γ-amino butyric acid or neuropeptide Y are suggested to be responsible for the pre-pubertal suppression of GnRH/gonadotropin secretion in primates. Taken together, the timing of pubertal onset is postulated to be controlled by upstream regulators for kisspeptin biosynthesis and secretion in mammals.
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Affiliation(s)
- Yoshihisa Uenoyama
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
- *Correspondence: Yoshihisa Uenoyama
| | - Naoko Inoue
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
| | - Sho Nakamura
- Faculty of Veterinary Medicine, Okayama University of Science, Imabari, Japan
| | - Hiroko Tsukamura
- Laboratory of Animal Reproduction, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan
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14
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Ozkanli S, Basar MM, Selimoglu S, Erol B, Ozkanli O, Nurili F, Kahraman S. The ghrelin and orexin activity in testicular tissues of patients with idiopathic non-obstructive azoospermia. Kaohsiung J Med Sci 2018; 34:564-568. [PMID: 30309484 DOI: 10.1016/j.kjms.2018.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 03/25/2018] [Accepted: 04/10/2018] [Indexed: 10/28/2022] Open
Abstract
The aim of the present study is to evaluate the presence of ghrelin and orexin in the testicular tissue of patients who have undergone microscopic testicular sperm extraction (micro-TESE) due to idiopathic non-obstructive azoospermia. Seventy azoospermic cases were included in this study; serum hormone levels were measured and genetic investigations were performed. The patients were divided into two groups: micro-TESE (+) and micro-TESE (-). The number of Leydig cells and stained cells in the seminiferous tubules were counted under a light microscope, and we analyzed ghrelin and orexin activity. The relationship between serum hormone levels and ghrelin and orexin distributions in testicular tissue was evaluated according to micro-TESE results. While sperm was found in 33 cases (47.1%), micro-TESE was negative in 37 cases (52.9%). Peptide hormone activity in testicular tissue was higher in micro-TESE (+) cases. However, interstitial orexin (p = 0.038) and ghrelin (p = 0.002) activity showed statistically meaningful differences. Many different peptides, genes, and other unknown mechanisms play important roles in testicular function. In particular, the peptides orexin and ghrelin may play regulatory roles in testicular function in humans.
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Affiliation(s)
- Seyma Ozkanli
- Department of Pathology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey.
| | | | | | - Bulent Erol
- Department of Urology, Faculty of Medicine, Istanbul Medeniyet University, Istanbul, Turkey
| | - Oguz Ozkanli
- Department of Anesthesiology, Memorial Sisli Hospital, Istanbul, Turkey
| | - Fuad Nurili
- Department of Radiology, Memorial Sloan Kettering Cancer Center, USA
| | - Semra Kahraman
- Department of IVF, Memorial Sisli Hospital, Istanbul, Turkey
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15
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Wang W, Chen ZX, Guo DY, Tao YX. Regulation of prostate cancer by hormone-responsive G protein-coupled receptors. Pharmacol Ther 2018; 191:135-147. [PMID: 29909235 DOI: 10.1016/j.pharmthera.2018.06.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 06/01/2018] [Indexed: 11/27/2022]
Abstract
Regulation of prostate cancer by androgen and androgen receptor (AR), and blockade of AR signaling by AR antagonists and steroidogenic enzyme inhibitors have been extensively studied. G protein-coupled receptors (GPCRs) are a family of membrane receptors that regulate almost all physiological processes. Nearly 40% of FDA-approved drugs in the market target GPCRs. A variety of GPCRs that mediate reproductive function have been demonstrated to be involved in the regulation of prostate cancer. These GPCRs include gonadotropin-releasing hormone receptor, luteinizing hormone receptor, follicle-stimulating hormone receptor, relaxin receptor, ghrelin receptor, and kisspeptin receptor. We highlight here GPCR regulation of prostate cancer by these GPCRs. Further therapeutic approaches targeting these GPCRs for the treatment of prostate cancer are summarized.
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Affiliation(s)
- Wei Wang
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China
| | - Zhao-Xia Chen
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China
| | - Dong-Yu Guo
- Department of Clinical Laboratory, Xiamen Huli Guoyu Clinic, Co., Ltd., Xiamen, China.
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, Alabama, USA.
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16
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Poretti MB, Frautschi C, Luque E, Bianconi S, Martini AC, Stutz G, Vincenti L, Santillán ME, Ponzio M, Schiöth HB, Fiol de Cuneo M, Carlini VP. Reproductive performance of male mice after hypothalamic ghrelin administration. Reproduction 2018; 156:121-132. [PMID: 29794024 DOI: 10.1530/rep-17-0535] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 05/22/2018] [Indexed: 12/17/2022]
Abstract
It has been demonstrated that food intake and reproductive physiology are both simultaneously modulated to optimize reproductive success under fluctuating metabolic conditions. Ghrelin (GHRL) is an orexigenic peptide identified as the endogenous ligand of the growth hormone secretagogue receptor that is being investigated for its potential role on reproduction. Considering that data available so far are still limited and characterization of GHRL action mechanism on the reproductive system has not been fully elucidated, we studied the participation of hypothalamus in GHRL effects on sperm functional activity, plasma levels of gonadotropins and histological morphology in mice testes after hypothalamic infusion of 0.3 or 3.0 nmol/day GHRL or artificial cerebrospinal fluid (ACSF) at different treatment periods. We found that GHRL 3.0 nmol/day administration for 42 days significantly reduced sperm concentration (GHRL 3.0 nmol/day = 14.05 ± 2.44 × 106/mL vs ACSF = 20.33 ± 1.35 × 106/mL, P < 0.05) and motility (GHRL 3.0 nmol/day = 59.40 ± 4.20% vs ACSF = 75.80 ± 1.40%, P < 0.05). In addition, histological studies showed a significant decrease percentage of spermatogonia (GHRL 3.0 nmol/day = 6.76 ± 0.68% vs ACSF = 9.56 ± 0.41%, P < 0.05) and sperm (GHRL 3.0 nmol/day = 24.24 ± 1.92% vs ACSF = 31.20 ± 3.06%, P < 0.05). These results were associated with a significant reduction in luteinizing hormone and testosterone plasma levels (P < 0.05). As GHRL is an orexigenic peptide, body weight and food intake were measured. Results showed that GHRL increases both parameters; however, the effect did not last beyond the first week of treatment. Results presented in this work confirm that central GHRL administration impairs spermatogenesis and suggest that this effect is mediated by inhibition of hypothalamic-pituitary-gonadal axis.
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Affiliation(s)
- María Belén Poretti
- INICSAFacultad de Ciencias Médicas (CONICET-FCM), Instituto de Fisiología, Córdoba, Argentina .,Department of NeuroscienceFunctional Pharmacology, Uppsala University, Uppsala, Sweden
| | - Camila Frautschi
- Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Eugenia Luque
- INICSAFacultad de Ciencias Médicas (CONICET-FCM), Instituto de Fisiología, Córdoba, Argentina
| | - Santiago Bianconi
- Department of NeuroscienceFunctional Pharmacology, Uppsala University, Uppsala, Sweden.,Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Ana Carolina Martini
- INICSAFacultad de Ciencias Médicas (CONICET-FCM), Instituto de Fisiología, Córdoba, Argentina
| | - Graciela Stutz
- Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Laura Vincenti
- Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Maria Emilia Santillán
- Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Marina Ponzio
- INICSAFacultad de Ciencias Médicas (CONICET-FCM), Instituto de Fisiología, Córdoba, Argentina
| | - Helgi B Schiöth
- Department of NeuroscienceFunctional Pharmacology, Uppsala University, Uppsala, Sweden
| | - Marta Fiol de Cuneo
- Facultad de Ciencias MédicasUniversidad Nacional de Córdoba, Cátedra de Fisiología Humana, Córdoba, Argentina
| | - Valeria Paola Carlini
- INICSAFacultad de Ciencias Médicas (CONICET-FCM), Instituto de Fisiología, Córdoba, Argentina.,Department of NeuroscienceFunctional Pharmacology, Uppsala University, Uppsala, Sweden
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KOŁODZIEJSKI PA, PRUSZYŃSKA-OSZMAŁEK E, KOREK E, SASSEK M, SZCZEPANKIEWICZ D, KACZMAREK P, NOGOWSKI L, MAĆKOWIAK P, NOWAK KW, KRAUSS H, STROWSKI MZ. Serum Levels of Spexin and Kisspeptin Negatively Correlate With Obesity and Insulin Resistance in Women. Physiol Res 2018; 67:45-56. [DOI: 10.33549/physiolres.933467] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Spexin (SPX) and kisspeptin (KISS) are novel peptides relevant in the context of regulation of metabolism, food intake, puberty and reproduction. Here, we studied changes of serum SPX and KISS levels in female non-obese volunteers (BMI<25 kg/m2) and obese patients (BMI>35 kg/m2). Correlations between SPX or KISS with BMI, McAuley index, QUICKI, HOMA IR, serum levels of insulin, glucagon, leptin, adiponectin, orexin-A, obestatin, ghrelin and GLP-1 were assessed. Obese patients had lower SPX and KISS levels as compared to non-obese volunteers (SPX: 4.48±0.19 ng/ml vs. 6.63±0.29 ng/ml; p<0.001, KISS: 1.357±0.15 nmol/l vs. 2.165±0.174 nmol/l; p<0.01). SPX negatively correlated with BMI, HOMA-IR, insulin, glucagon, active ghrelin and leptin. Positive correlations were found between SPX and QUICKI index, McAuley index, serum levels of obestatin, GLP-1 and adiponectin and orexin-A Serum KISS negatively correlated with BMI, HOMA-IR, serum levels of insulin, glucagon, active ghrelin and leptin. KISS positively correlated with QUICKI index, McAuley index and adiponectin. In summary, SPX and KISS show negative correlations with obesity, insulin resistance indices, and hormones known to affect insulin sensitivity in females. Both, SPX and KISS could be therefore relevant in the pathophysiology of obesity and insulin resistance.
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Affiliation(s)
- P. A. KOŁODZIEJSKI
- Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland
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Camargo-Silva G, Turones LC, da Cruz KR, Gomes KP, Mendonça MM, Nunes A, de Jesus IG, Colugnati DB, Pansani AP, Pobbe RLH, Santos R, Fontes MAP, Guatimosim S, de Castro CH, Ianzer D, Ferreira RN, Xavier CH. Ghrelin potentiates cardiac reactivity to stress by modulating sympathetic control and beta-adrenergic response. Life Sci 2018; 196:84-92. [PMID: 29366747 DOI: 10.1016/j.lfs.2018.01.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/10/2018] [Accepted: 01/18/2018] [Indexed: 02/07/2023]
Abstract
Prior evidence indicates that ghrelin is involved in the integration of cardiovascular functions and behavioral responses. Ghrelin actions are mediated by the growth hormone secretagogue receptor subtype 1a (GHS-R1a), which is expressed in peripheral tissues and central areas involved in the control of cardiovascular responses to stress. AIMS In the present study, we assessed the role of ghrelin - GHS-R1a axis in the cardiovascular reactivity to acute emotional stress in rats. MAIN METHODS AND KEY FINDINGS Ghrelin potentiated the tachycardia evoked by restraint and air jet stresses, which was reverted by GHS-R1a blockade. Evaluation of the autonomic balance revealed that the sympathetic branch modulates the ghrelin-evoked positive chronotropy. In isolated hearts, the perfusion with ghrelin potentiated the contractile responses caused by stimulation of the beta-adrenergic receptor, without altering the amplitude of the responses evoked by acetylcholine. Experiments in isolated cardiomyocytes revealed that ghrelin amplified the increases in calcium transient changes evoked by isoproterenol. SIGNIFICANCE Taken together, our results indicate that the Ghrelin-GHS-R1a axis potentiates the magnitude of stress-evoked tachycardia by modulating the autonomic nervous system and peripheral mechanisms, strongly relying on the activation of cardiac calcium transient and beta-adrenergic receptors.
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Affiliation(s)
- Gabriel Camargo-Silva
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Larissa Córdova Turones
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Kellen Rosa da Cruz
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Karina Pereira Gomes
- Integrative Laboratory of Cardiovascular and Neurological Pathophysiology, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Michelle Mendanha Mendonça
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Allancer Nunes
- Integrative Laboratory of Cardiovascular and Neurological Pathophysiology, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Itamar Guedes de Jesus
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Diego Basile Colugnati
- Integrative Laboratory of Cardiovascular and Neurological Pathophysiology, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Aline Priscila Pansani
- Integrative Laboratory of Cardiovascular and Neurological Pathophysiology, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Roger Luis Henschel Pobbe
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Robson Santos
- National Institute of Science and Technology Nanobiopharmaceutics (INCT NanoBioFar), Brazil
| | | | - Silvia Guatimosim
- Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil; National Institute of Science and Technology Nanobiopharmaceutics (INCT NanoBioFar), Brazil
| | - Carlos Henrique de Castro
- Integrative Laboratory of Cardiovascular and Neurological Pathophysiology, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil; National Institute of Science and Technology Nanobiopharmaceutics (INCT NanoBioFar), Brazil
| | - Danielle Ianzer
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil; National Institute of Science and Technology Nanobiopharmaceutics (INCT NanoBioFar), Brazil
| | - Reginaldo Nassar Ferreira
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil
| | - Carlos Henrique Xavier
- Laboratory of Cardiovascular Physiology and Therapeutics, Department of Physiological Sciences, Institute of Biological Sciences, Federal University of Goiás, Goiania, GO, Brazil; National Institute of Science and Technology Nanobiopharmaceutics (INCT NanoBioFar), Brazil.
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The presence of acylated ghrelin during in vitro maturation of bovine oocytes induces cumulus cell DNA damage and apoptosis, and impairs early embryo development. ZYGOTE 2017; 25:601-611. [PMID: 28929981 DOI: 10.1017/s0967199417000478] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of this study was to investigate the effects of acylated ghrelin supplementation during in vitro maturation (IVM) of bovine oocytes. IVM medium was supplemented with 20, 40 or 60 pM acylated ghrelin concentrations. Cumulus expansion area and oocyte nuclear maturation were studied as maturation parameters. Cumulus-oocyte complexes (COC) were assessed with the comet, apoptosis and viability assays. The in vitro effects of acylated ghrelin on embryo developmental capacity and embryo quality were also evaluated. Results demonstrated that acylated ghrelin did not affect oocyte nuclear maturation and cumulus expansion area. However, it induced cumulus cell (CC) death, apoptosis and DNA damage. The damage increased as a function of the concentration employed. Additionally, the percentages of blastocyst yield, hatching and embryo quality decreased with all acylated ghrelin concentrations tested. Our study highlights the importance of acylated ghrelin in bovine reproduction, suggesting that this metabolic hormone could function as a signal that prevents the progress to reproductive processes.
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Torsoni MA, Borges BC, Cote JL, Allen SJ, Mahany E, Garcia-Galiano D, Elias CF. AMPKα2 in Kiss1 Neurons Is Required for Reproductive Adaptations to Acute Metabolic Challenges in Adult Female Mice. Endocrinology 2016; 157:4803-4816. [PMID: 27732087 PMCID: PMC5133340 DOI: 10.1210/en.2016-1367] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A temporary and reversible inhibition of the hypothalamo-pituitary-gonadal axis is adaptive when energy reserves are diminished, allowing individual survival and energy accumulation for eventual reproduction. The AMP-activated protein kinase (AMPK) works as a cellular sensor of the AMP to ATP ratio and ultimately of energy availability. Activation of AMPK suppresses ATP-consuming processes and stimulates ATP-producing pathways. The AMPK α2 catalytic subunit is expressed in multiple hypothalamic nuclei including those associated with reproductive control, ie, the anteroventral periventricular nucleus and the arcuate nucleus. Subsets of kisspeptin neurons in the anteroventral periventricular nucleus (20% in females) and arcuate nucleus (45% in males and 65% in females) coexpress AMPKα2 mRNA. Using the Cre-loxP approach, we assessed whether AMPKα2 in Kiss1 cells is required for body weight and reproductive function. The AMPKα2-deleted mice show no difference in body weight and time for sexual maturation compared with controls. Males and females are fertile and have normal litter size. The AMPKα2-deleted and control females have similar estradiol feedback responses and show no difference in Kiss1 mRNA expression after ovariectomy or ovariectomy plus estradiol replacement. In males, acute fasting decreased Kiss1 mRNA expression in both groups, but no effect was observed in females. However, after an acute fasting, control mice displayed prolonged diestrous phase, but AMPKα2-deleted females showed no disruption of estrous cycles. Our findings demonstrate that the AMPKα2 catalytic subunit in Kiss1 cells is dispensable for body weight and reproductive function in mice but is necessary for the reproductive adaptations to conditions of acute metabolic distress.
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Affiliation(s)
- Marcio A Torsoni
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - Beatriz C Borges
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - Jessica L Cote
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - Susan J Allen
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - Erica Mahany
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - David Garcia-Galiano
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
| | - Carol F Elias
- Laboratory of Metabolism Disorders (M.A.T.), School of Applied Sciences, State University of Campinas, Limeira-SP 13484-350, Brazil; and Department of Molecular and Integrative Physiology (M.A.T., B.C.B., S.J.A., D.G.-G., C.F.E.), Neuroscience Graduate Program (J.L.C.), and Department of Obstetrics and Gynecology (E.M., C.F.E.), University of Michigan, Ann Arbor, Michigan 48109
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Gavela-Pérez T, Navarro P, Soriano-Guillén L, Garcés C. High Prepubertal Leptin Levels Are Associated With Earlier Menarcheal Age. J Adolesc Health 2016; 59:177-81. [PMID: 27297138 DOI: 10.1016/j.jadohealth.2016.03.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 03/17/2016] [Accepted: 03/19/2016] [Indexed: 01/09/2023]
Abstract
PURPOSE Given the interplay between metabolic status and the reproductive system, factors governing energy homeostasis could influence the timing of pubertal onset. The aim of this longitudinal study was to determine the influence of metabolic peptides associated to adiposity on menarcheal age. METHODS The sample population included 168 girls. Anthropometric and biochemical variables were measured at a prepubertal baseline (6-8 years old) and 7 years later. Leptin and adiponectin levels were determined by Enzyme-Linked ImmunoSorbent Assay, insulin by radioimmunoassay and ghrelin by a multiplexed bead immunoassay. RESULTS Adjusted for body mass index, Spearman correlation analysis revealed a significant negative association between prepubertal leptin levels and menarche. The highest prepubertal leptin levels were observed in overweight girls with the earliest menarche. Menarcheal age was significantly associated with variation of adiponectin levels between both baseline and follow-up. Multiple regression analysis showed that prepubertal leptin was the only significant contributing factor, predicting 15.3% of variation in menarcheal age. CONCLUSIONS High leptin levels in prepubertal girls are associated with earlier menarcheal age, independent of body mass index. However, the relationship of ghrelin, insulin, or adiponectin levels with menarcheal age is not evident in our population.
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Affiliation(s)
- Teresa Gavela-Pérez
- Lipid Research Laboratory, IIS-Fundación Jimenez Díaz, Madrid, Spain; Department of Pediatrics, IIS-Fundación Jimenez Díaz, Madrid, Spain
| | - Pilar Navarro
- Lipid Research Laboratory, IIS-Fundación Jimenez Díaz, Madrid, Spain
| | - Leandro Soriano-Guillén
- Lipid Research Laboratory, IIS-Fundación Jimenez Díaz, Madrid, Spain; Department of Pediatrics, IIS-Fundación Jimenez Díaz, Madrid, Spain
| | - Carmen Garcés
- Lipid Research Laboratory, IIS-Fundación Jimenez Díaz, Madrid, Spain.
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22
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Edwards A, Abizaid A. Driving the need to feed: Insight into the collaborative interaction between ghrelin and endocannabinoid systems in modulating brain reward systems. Neurosci Biobehav Rev 2016; 66:33-53. [PMID: 27136126 DOI: 10.1016/j.neubiorev.2016.03.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 03/08/2016] [Accepted: 03/31/2016] [Indexed: 01/29/2023]
Abstract
Independent stimulation of either the ghrelin or endocannabinoid system promotes food intake and increases adiposity. Given the similar distribution of their receptors in feeding associated brain regions and organs involved in metabolism, it is not surprising that evidence of their interaction and its importance in modulating energy balance has emerged. This review documents the relationship between ghrelin and endocannabinoid systems within the periphery and hypothalamus (HYP) before presenting evidence suggesting that these two systems likewise work collaboratively within the ventral tegmental area (VTA) to modulate non-homeostatic feeding. Mechanisms, consistent with current evidence and local infrastructure within the VTA, will be proposed.
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Affiliation(s)
- Alexander Edwards
- Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
| | - Alfonso Abizaid
- Department of Neuroscience, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada.
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23
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Ristic N, Stevanovic D, Nesic D, Ajdzanovic V, Rakocevic R, Jaric I, Milosevic V. Diet-Induced Obesity and Ghrelin Effects on Pituitary Gonadotrophs: Immunohistomorphometric Study in Male Rats. CELL JOURNAL 2016; 17:711-9. [PMID: 26862530 PMCID: PMC4746421 DOI: 10.22074/cellj.2016.3843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 02/24/2015] [Indexed: 11/12/2022]
Abstract
Objective The close relationship between energy metabolism, nutritional state, and
reproductive physiology suggests that nutritional and metabolic disorders can disrupt
normal reproductive function and fertility. Considering the importance of leptin and
ghrelin effects in regulation of the hypothalamic-pituitary-gonadal axis, the objective
of this study was to investigate the influence of obesity and centrally applied ghrelin
on immunohistochemical appearance and quantitative morphology of the pituitary
follicle-stimulating hormone (FSH) and luteinizing hormone (LH) producing cells in
adult male rats. Materials and Methods In this experimental study, animals were given two differ-
ent diets: normal-fat (NF) and high-fat (HF), for 4 weeks, corresponding to normal
and positive energy balance (n=2×14), respectively. Each group was subsequently
divided into two subgroups (n=7) receiving intracerebroventricular (ICV) injections of
either ghrelin [G, 1 µg/5 µL phosphate buffered saline (PBS)] or vehicle (5 µL PBS,
control group) every 24 hours for five consecutive days.
Results Morphometric analyses showed that in HF control group, the percentage of
FSH cells per unit volume of total pituitary gland tissue (in μm3), i.e. volume density
(Vvc), was increased (P<0.05) by 9.1% in comparison with the NF controls. After
ICV treatment with ghrelin, volume (Vc) and volume density (Vvc) of FSH cells in
ghrelin+NF (GNF) and ghrelin+HF (GHF) groups remained unchanged in comparison
with NF and HF controls. Volume of LH cells in HF control group was increased by
17% (P<0.05), but their Vvc was decreased by 8.3% (P<0.05) in comparison with
NF controls. In GNF group, the volume of LH cells increased by 7% (P<0.05), in
comparison with the NF controls, but in GHF group, the same parameter remained
unchanged when compared with HF controls. The central application of ghrelin de-
creased the Vvc of LH cells only in GNF group by 38.9% (P<0.05) in comparison with
the NF control animals.
Conclusion The present study has shown that obesity and repetitive ICV administra-
tion of low doses of ghrelin, in NF and HF rats, modulated the immunohistomorphometric
features of gonadotrophs, indicating the importance of obesity and ghrelin in regulation of
the reproductive function.
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Affiliation(s)
- Natasa Ristic
- Institute for Biological Research Sinisa Stankovic, University of Belgrade, Belgrade, Serbia
| | - Darko Stevanovic
- Institute of Medical Physiology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Dejan Nesic
- Institute of Medical Physiology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Vladimir Ajdzanovic
- Institute for Biological Research Sinisa Stankovic, University of Belgrade, Belgrade, Serbia
| | - Rastko Rakocevic
- Institute of Medical Physiology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Ivana Jaric
- Institute for Biological Research Sinisa Stankovic, University of Belgrade, Belgrade, Serbia
| | - Verica Milosevic
- Institute for Biological Research Sinisa Stankovic, University of Belgrade, Belgrade, Serbia
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Abstract
The purpose of this review is to draw attention to the limited information available on food intake (FI) control in children and adolescents 7-17 y of age, which is essential for developing food policies and guidelines in this population. Although environmental factors have been the overwhelming focus of research on the causative factors of obesity, research focusing on the physiologic control of appetite in children and adolescents is a neglected area of research. To present this message, a review of FI regulation and the role of food and food components in signaling processes are followed by an examination of the role of hormones during puberty in intake regulation. To examine the interaction of environment and physiology on FI regulation, the effects of exercise, television programs, and food advertisements are discussed. In conclusion, although limited, this literature review supports a need for children and adolescents to be a greater focus of research that would lead to sound nutrition policies and actions to reduce chronic disease. A focus on the environment must be balanced with an understanding of physiologic and behavioral changes associated with this age group.
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Affiliation(s)
- G Harvey Anderson
- Department for Nutritional Sciences and Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Canada
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25
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Outeiriño-Iglesias V, Romaní-Pérez M, González-Matías LC, Vigo E, Mallo F. GLP-1 Increases Preovulatory LH Source and the Number of Mature Follicles, As Well As Synchronizing the Onset of Puberty in Female Rats. Endocrinology 2015; 156:4226-37. [PMID: 26252058 DOI: 10.1210/en.2014-1978] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Control of estrous cycle and reproductive capacity involves a large number of central and peripheral factors, integrating numerous nutritional and metabolic signals. Here we show that glucagon-like peptide-1 (GLP-1), a peptide with anorexigenic and insulinotropic actions, and the GLP-1 receptor agonist Exendin-4 (Ex4) exert a regulatory influence on the gonadal axis, in both adult and prepubertal female rats. In adult rats, Glp-1 receptor expression varies during the estrous cycle at the hypothalamus, pituitary, and ovary. Furthermore, acute treatment with GLP-1 in the morning proestrus doubled the amplitude of the preovulatory LH surge, as well as influencing estradiol and progesterone levels along the estrous cycle. These changes provoked an important increase in the number of Graafian follicles and corpora lutea, as well as in the litter size. Conversely, Ex4 diminished the levels of LH, later producing a partial blockade at the preovulatory surge, yet not affecting either the number of mature follicles or corpora lutea. Chronic administration of low doses of GLP-1 to prepubertal rats synchronized vaginal opening and increased LH levels on the 35th day of life, yet at these doses it did not modify their body weight, food intake, or ovarian and uterine weight. By contrast, chronic exposure to Ex4 produced a significant reduction in ovarian and uterine weight, and serum LH, and the animals treated chronically with Ex4 showed no vaginal opening in the period studied. Overall, our results demonstrate that GLP-1 and Ex4 act on the gonadal axis, involving the hypothalamic kisspeptin system, to influence reproductive efficiency in female rats.
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Affiliation(s)
- Verónica Outeiriño-Iglesias
- Laboratory of Endocrinology, Biomedical Research Centre (Centro Investigaciones Biomédicas), University of Vigo, Campus As Lagoas-Marcosende, E-36310 Vigo, Spain; and Institute for Biomedical Research of Vigo, E-36310 Vigo, Spain
| | - Marina Romaní-Pérez
- Laboratory of Endocrinology, Biomedical Research Centre (Centro Investigaciones Biomédicas), University of Vigo, Campus As Lagoas-Marcosende, E-36310 Vigo, Spain; and Institute for Biomedical Research of Vigo, E-36310 Vigo, Spain
| | - Lucas C González-Matías
- Laboratory of Endocrinology, Biomedical Research Centre (Centro Investigaciones Biomédicas), University of Vigo, Campus As Lagoas-Marcosende, E-36310 Vigo, Spain; and Institute for Biomedical Research of Vigo, E-36310 Vigo, Spain
| | - Eva Vigo
- Laboratory of Endocrinology, Biomedical Research Centre (Centro Investigaciones Biomédicas), University of Vigo, Campus As Lagoas-Marcosende, E-36310 Vigo, Spain; and Institute for Biomedical Research of Vigo, E-36310 Vigo, Spain
| | - Federico Mallo
- Laboratory of Endocrinology, Biomedical Research Centre (Centro Investigaciones Biomédicas), University of Vigo, Campus As Lagoas-Marcosende, E-36310 Vigo, Spain; and Institute for Biomedical Research of Vigo, E-36310 Vigo, Spain
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26
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Ghrelin receptor in Japanese fire belly newt, Cynops pyrrhogaster. Comp Biochem Physiol B Biochem Mol Biol 2015; 189:15-22. [DOI: 10.1016/j.cbpb.2015.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Revised: 06/19/2015] [Accepted: 07/03/2015] [Indexed: 12/20/2022]
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Roa J, Tena-Sempere M. Connecting metabolism and reproduction: roles of central energy sensors and key molecular mediators. Mol Cell Endocrinol 2014; 397:4-14. [PMID: 25289807 DOI: 10.1016/j.mce.2014.09.027] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/26/2014] [Accepted: 09/26/2014] [Indexed: 12/15/2022]
Abstract
It is well established that pubertal activation of the reproductive axis and maintenance of fertility are critically dependent on the magnitude of body energy reserves and the metabolic state of the organism. Hence, conditions of impaired energy homeostasis often result in deregulation of puberty and reproduction, whereas gonadal dysfunction can be associated with the worsening of the metabolic profile and, eventually, changes in body weight. While much progress has taken place in our knowledge about the neuroendocrine mechanisms linking metabolism and reproduction, our understanding of how such dynamic interplay happens is still incomplete. As paradigmatic example, much has been learned in the last two decades on the reproductive roles of key metabolic hormones (such as leptin, insulin and ghrelin), their brain targets and the major transmitters and neuropeptides involved. Yet, the molecular mechanisms whereby metabolic information is translated and engages into the reproductive circuits remain largely unsolved. In this work, we will summarize recent developments in the characterization of the putative central roles of key cellular energy sensors, such as mTOR, in this phenomenon, and will relate these with other molecular mechanisms likely contributing to the brain coupling of energy balance and fertility. In doing so, we aim to provide an updated view of an area that, despite still underdeveloped, may be critically important to fully understand how reproduction and metabolism are tightly connected in health and disease.
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Affiliation(s)
- Juan Roa
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Cordoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Córdoba, Spain; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)/Hospital Universitario Reina Sofia, 14004 Córdoba, Spain
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Cordoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Córdoba, Spain; Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)/Hospital Universitario Reina Sofia, 14004 Córdoba, Spain.
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Wolfe A, Divall S, Wu S. The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1). Front Neuroendocrinol 2014; 35:558-72. [PMID: 24929098 PMCID: PMC4175134 DOI: 10.1016/j.yfrne.2014.05.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 04/01/2014] [Accepted: 05/27/2014] [Indexed: 12/27/2022]
Abstract
The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction.
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Affiliation(s)
- Andrew Wolfe
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States.
| | - Sara Divall
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States
| | - Sheng Wu
- Johns Hopkins University School of Medicine, Department of Pediatrics, Division of Endocrinology, Baltimore, MD 21287, United States
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29
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Catak Z, Aydin S, Sahin I, Kuloglu T, Aksoy A, Dagli AF. Regulatory neuropeptides (ghrelin, obestatin and nesfatin-1) levels in serum and reproductive tissues of female and male rats with fructose-induced metabolic syndrome. Neuropeptides 2014; 48:167-77. [PMID: 24786976 DOI: 10.1016/j.npep.2014.04.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/02/2014] [Accepted: 04/07/2014] [Indexed: 12/15/2022]
Abstract
Although, the exact mechanisms underlying the development of the metabolic syndrome (MetS) are not still completely understood, obesity, circulated peptide hormone levels and their interaction with genetic factors are considered largely responsible. The purpose of this study is to explore how the levels of ghrelin, obestatin (OBS) and NUCB2/nesfatin-1 (NES)/NUCB2 change in serum and the reproductive tissues of female and male rats with fructose-induced metabolic syndrome, and whether the levels of each hormone is correlated with the hormones involved with fertility. Experiments were conducted on 5-week-old Sprague-Dawley male and female rats assigned to either a control group or a MetS group. Controls were fed standard rat food and water ad libitum, while the MetS group was fed standard food with 10% (v/v) fructose solution added to their drinking water for 12 weeks with a 12/12h photoperiod circle. Then, all animals were sacrificed after a one night fast. Peptides levels in the serum and reproductive tissues of rats were studied using the ELISA method while the immunoreactivity of reproductive system peptide hormones were shown by immunohistochemical staining method. Furthermore, the other biochemical parameters were measured using Konelab-60 equipment and infertility hormones were measured with Immulite2000. Fasting serum insulin, glucose, triglyceride, alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) levels were statistically significantly higher, and the amount of high density lipoprotein cholesterol (HDL-C) was significantly lower, in the MetS groups. Serum and tissue supernatant NES levels were significantly higher in the rats with MetS than the control group. Ghrelin, OBS and NES were expressed in the cytoplasm, concentrated around the apical parts of the epithelial cells in the reproductive tissues of the rats. The amounts of ghrelin were lower in the reproductive tissues of the animals with MetS, while NES levels in the same tissues increased. Obestatin also decreased, though not in the seminal glands.
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Affiliation(s)
- Zekiye Catak
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey
| | - Suleyman Aydin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey.
| | - Ibrahim Sahin
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Histology and Embryology, Medical School, Erzincan University, 24030 Erzincan, Turkey
| | - Tuncay Kuloglu
- Department of Histology and Embryology, Medical School, Firat University, 23119 Elazig, Turkey
| | - Aziz Aksoy
- Department of Medical Biochemistry and Clinical Biochemistry (Firat Hormones Research Group), Medical School, Firat University, 23119 Elazig, Turkey; Department of Nutrition and Dietetics, Bitlis Eren University, 13000 Bitlis, Turkey
| | - Adile Ferda Dagli
- Department of Medical Pathology, Medical School, Inonu University, 44280 Malatya, Turkey
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Upregulation and nuclear translocation of testicular ghrelin protects differentiating spermatogonia from ionizing radiation injury. Cell Death Dis 2014; 5:e1248. [PMID: 24853426 PMCID: PMC4047875 DOI: 10.1038/cddis.2014.223] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/13/2014] [Accepted: 04/18/2014] [Indexed: 11/13/2022]
Abstract
Proper control of apoptotic signaling is important for maintenance of testicular homeostasis after ionizing radiation (IR). Herein, we challenged the hypothesis that ghrelin, a pleiotropic modulator, is potentially involved in IR-induced germ cell injury. Lower body exposure to 2 Gy of IR induced a notable increase of ghrelin expression in the nuclear of differentiating spermatogonia at defined stages, with an impairment in the Leydig cells (LCs)-expressing ghrelin. Unexpectedly, inhibition of the ghrelin pathway by intraperitoneal injection of a specific GHS-R1α antagonist enhanced spermatogonia elimination by apoptosis during the early recovery following IR, and thereafter resulted in impaired male fertility, suggesting that the anti-apoptotic effects of evoked ghrelin, although transient along testicular IR injury, have a profound influence on the post-injury recovery. In addition, inhibition of ghrelin signaling resulted in a significant increase in the intratesticular testosterone (T) level at the end of 21 days after IR, which should stimulate the spermatogenic recovery from surviving spermatogonia to a certain extent during the late stage. We further demonstrated that the upregulation and nuclear trafficking of ghrelin, elaborately regulated by IR-elicited antioxidant system in spermatogonia, may act through a p53-dependent mechanism. The elicitation of ghrelin expression by IR stress, the regulation of ghrelin expression by IR-induced oxidative stress and the interaction between p53 and ghrelin signaling during IR injury were confirmed in cultured spermatogonia. Hence, our results represent the first evidence in support of a radioprotective role of ghrelin in the differentiating spermatogonia. The acutely, delicate regulation of local-produced ghrelin appears to be a fine-tune mechanism modulating the balance between testicular homeostasis and early IR injury.
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31
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Luque EM, Torres PJ, de Loredo N, Vincenti LM, Stutz G, Santillán ME, Ruiz RD, de Cuneo MF, Martini AC. Role of ghrelin in fertilization, early embryo development, and implantation periods. Reproduction 2014; 148:159-67. [PMID: 24821833 DOI: 10.1530/rep-14-0129] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In order to clarify the physiological role of ghrelin in gestation, we evaluated the effects of administration of exogenous ghrelin (2 or 4 nmol/animal per day) or its antagonist (6 nmol/animal per day of (d-Lys3)GHRP6) on fertilization, early embryo development, and implantation periods in mice. Three experiments were performed, treating female mice with ghrelin or its antagonist: i) starting from 1 week before copulation to 12 h after copulation, mice were killed at day 18 of gestation; ii) since ovulation induction until 80 h later, when we retrieved the embryos from oviducts/uterus, and iii) starting from days 3 to 7 of gestation (peri-implantation), mice were killed at day 18. In experiments 1 and 3, the antagonist and/or the highest dose of ghrelin significantly increased the percentage of atrophied fetuses and that of females exhibiting this finding or a higher amount of corpora lutea compared with fetuses (nCL/nF) (experiment 3: higher nCL/nF-atrophied fetuses: ghrelin 4, 71.4-71.4% and antagonist, 75.0-62.5% vs ghrelin 2, 46.2-15.4% and control, 10-0.0%; n=7-13 females/group; P<0.01). In experiment 2, the antagonist diminished the fertilization rate, and both, ghrelin and the antagonist, delayed embryo development (blastocysts: ghrelin 2, 62.5%; ghrelin 4, 50.6%; and antagonist, 61.0% vs control 78.4%; n=82-102 embryos/treatment; P<0.0001). In experiment 3, additionally, ghrelin (4 nmol/day) and the antagonist significantly diminished the weight gain of fetuses and dams during pregnancy. Our results indicate that not only hyperghrelinemia but also the inhibition of the endogenous ghrelin effects exerts negative effects on the fertilization, implantation, and embryo/fetal development periods, supporting the hypothesis that ghrelin (in 'adequate' concentrations) has a physiological role in early gestational events.
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Affiliation(s)
- Eugenia Mercedes Luque
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Pedro Javier Torres
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Nicolás de Loredo
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Laura María Vincenti
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Graciela Stutz
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - María Emilia Santillán
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Rubén Daniel Ruiz
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Marta Fiol de Cuneo
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
| | - Ana Carolina Martini
- Facultad de Ciencias MédicasInstituto de Fisiología, Universidad Nacional de Córdoba, Santa Rosa 1085, X5000ESU Córdoba, Argentina
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Frazao R, Dungan Lemko HM, da Silva RP, Ratra DV, Lee CE, Williams KW, Zigman JM, Elias CF. Estradiol modulates Kiss1 neuronal response to ghrelin. Am J Physiol Endocrinol Metab 2014; 306:E606-14. [PMID: 24473434 PMCID: PMC3948981 DOI: 10.1152/ajpendo.00211.2013] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Ghrelin is a metabolic signal regulating energy homeostasis. Circulating ghrelin levels rise during starvation and fall after a meal, and therefore, ghrelin may function as a signal of negative energy balance. Ghrelin may also act as a modulator of reproductive physiology, as acute ghrelin administration suppresses gonadotropin secretion and inhibits the neuroendocrine reproductive axis. Interestingly, ghrelin's effect in female metabolism varies according to the estrogen milieu predicting an interaction between ghrelin and estrogens, likely at the hypothalamic level. Here, we show that ghrelin receptor (GHSR) and estrogen receptor-α (ERα) are coexpressed in several hypothalamic sites. Higher levels of circulating estradiol increased the expression of GHSR mRNA and the coexpression of GHSR mRNA and ERα selectively in the arcuate nucleus (ARC). Subsets of preoptic and ARC Kiss1 neurons coexpressed GHSR. Increased colocalization was observed in ARC Kiss1 neurons of ovariectomized estradiol-treated (OVX + E₂; 80%) compared with ovariectomized oil-treated (OVX; 25%) mice. Acute actions of ghrelin on ARC Kiss1 neurons were also modulated by estradiol; 75 and 22% of Kiss1 neurons of OVX + E₂ and OVX mice, respectively, depolarized in response to ghrelin. Our findings indicate that ghrelin and estradiol may interact in several hypothalamic sites. In the ARC, high levels of E₂ increase GHSR mRNA expression, modifying the colocalization rate with ERα and Kiss1 and the proportion of Kiss1 neurons acutely responding to ghrelin. Our findings indicate that E₂ alters the responsiveness of kisspeptin neurons to metabolic signals, potentially acting as a critical player in the metabolic control of the reproductive physiology.
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Affiliation(s)
- Renata Frazao
- Department of Internal Medicine, Division of Hypothalamic Research, University of Texas Southwestern Medical Center, Dallas, Texas
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Farkas I, Vastagh C, Sárvári M, Liposits Z. Ghrelin decreases firing activity of gonadotropin-releasing hormone (GnRH) neurons in an estrous cycle and endocannabinoid signaling dependent manner. PLoS One 2013; 8:e78178. [PMID: 24124622 PMCID: PMC3790731 DOI: 10.1371/journal.pone.0078178] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 09/16/2013] [Indexed: 12/11/2022] Open
Abstract
The orexigenic peptide, ghrelin is known to influence function of GnRH neurons, however, the direct effects of the hormone upon these neurons have not been explored, yet. The present study was undertaken to reveal expression of growth hormone secretagogue receptor (GHS-R) in GnRH neurons and elucidate the mechanisms of ghrelin actions upon them. Ca2+-imaging revealed a ghrelin-triggered increase of the Ca2+-content in GT1-7 neurons kept in a steroid-free medium, which was abolished by GHS-R-antagonist JMV2959 (10µM) suggesting direct action of ghrelin. Estradiol (1nM) eliminated the ghrelin-evoked rise of Ca2+-content, indicating the estradiol dependency of the process. Expression of GHS-R mRNA was then confirmed in GnRH-GFP neurons of transgenic mice by single cell RT-PCR. Firing rate and burst frequency of GnRH-GFP neurons were lower in metestrous than proestrous mice. Ghrelin (40nM-4μM) administration resulted in a decreased firing rate and burst frequency of GnRH neurons in metestrous, but not in proestrous mice. Ghrelin also decreased the firing rate of GnRH neurons in males. The ghrelin-evoked alterations of the firing parameters were prevented by JMV2959, supporting the receptor-specific actions of ghrelin on GnRH neurons. In metestrous mice, ghrelin decreased the frequency of GABAergic mPSCs in GnRH neurons. Effects of ghrelin were abolished by the cannabinoid receptor type-1 (CB1) antagonist AM251 (1µM) and the intracellularly applied DAG-lipase inhibitor THL (10µM), indicating the involvement of retrograde endocannabinoid signaling. These findings demonstrate that ghrelin exerts direct regulatory effects on GnRH neurons via GHS-R, and modulates the firing of GnRH neurons in an ovarian-cycle and endocannabinoid dependent manner.
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Affiliation(s)
- Imre Farkas
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
- * E-mail:
| | - Csaba Vastagh
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Miklós Sárvári
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Zsolt Liposits
- Laboratory of Endocrine Neurobiology, Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
- Department of Neuroscience, Faculty of Information Technology, Pázmány Péter Catholic University, Budapest, Hungary
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Zhu CC, Zhang H, Zhang JS, Li Z, Zhao J, Li W, Zhang YQ. Inhibition of ghrelin signaling improves the reproductive phenotype of male ob/ob mouse. Fertil Steril 2012; 99:918-26. [PMID: 23232360 DOI: 10.1016/j.fertnstert.2012.11.022] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 11/12/2012] [Accepted: 11/12/2012] [Indexed: 10/27/2022]
Abstract
OBJECTIVE To investigate whether ghrelin signaling is involved in the pathogenesis of male factor infertility induced by leptin deficiency. DESIGN Experimental study. SETTING University academic medical center. ANIMAL(S) Ten-week-old C57BL/6J mice and ob/ob mice. INTERVENTION(S) Western blotting, (quantitative) reverse transcription-polymerase chain reaction (qRT-PCR), immunohistochemistry, and in situ end labeling of fragmented DNA. MAIN OUTCOME MEASURE(S) Expression levels of ghrelin and its functional receptor growth hormone (GH) secretagogue receptor 1a (GHS-R1α) were examined by Western blotting and immunohistochemistry. Ob/ob mice were injected IP with specific GHS-R1α antagonist, and thereafter germ cell apoptosis and steroidogenic capability were assessed by TUNEL assay, (q) RT-PCR, and radioimmunoassay. RESULT(S) Expression of GHS-R1α and its endogenous ligand ghrelin was both up-regulated in ob/ob testis. Inhibition of the ghrelin pathway restored androgen synthesis, reduced germ cell apoptosis, and thereby resulted in improved sperm production in ob/ob mice. CONCLUSION(S) Ghrelin, as an antagonistic partner of leptin in the endocrinic/paracrine circuit, may be involved in the pathogenesis of male factor infertility induced by leptin deficiency.
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Affiliation(s)
- Chu-Chao Zhu
- Department of Human Anatomy and Histology and Embryology, the Fourth Military Medical University, Xian, People's Republic of China
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Delhanty PJD, Neggers SJ, van der Lely AJ. Mechanisms in endocrinology: Ghrelin: the differences between acyl- and des-acyl ghrelin. Eur J Endocrinol 2012; 167:601-8. [PMID: 22898499 DOI: 10.1530/eje-12-0456] [Citation(s) in RCA: 170] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Des-acyl ghrelin (DAG) is one of the three preproghrelin gene-encoded peptides. Compared with ghrelin and obestatin, it has not received the attention it deserves. DAG has long been considered an inert degradation product of acyl ghrelin (AG). Recent evidence, however, indicates that DAG behaves like a separate hormone. DAG can act together with AG, can antagonize AG, and seems to have AG-independent effects. Therefore, it is believed that DAG must activate its own receptor and that it may also interact with AG at this receptor. Of potential clinical importance is that an increasing number of studies suggest that DAG might be a functional inhibitor of ghrelin and that DAG can suppress ghrelin levels in humans. Therefore, DAG or DAG analogs might be good candidates for future treatment of metabolic disorders or other conditions in which antagonism of AG actions could be beneficial, such as diabetes, obesity, and Prader-Willi syndrome.
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Affiliation(s)
- Patric J D Delhanty
- Department of Medicine, Erasmus University MC, CA Rotterdam, The Netherlands
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Fang F, Liu Y, Zhao X, Li Y, Zhang Y, Zhang X. The association between testicular ghrelin receptor mRNA and serum testosterone levels in immunocastrated boars. Anim Reprod Sci 2012; 135:62-7. [PMID: 23021962 DOI: 10.1016/j.anireprosci.2012.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 09/06/2012] [Accepted: 09/07/2012] [Indexed: 10/27/2022]
Abstract
Ghrelin, the endogenous ligand for the GH secretagogue receptor (GHS-R), has various functions. The expression of ghrelin and growth hormone secretagogue receptor type 1a (GHS-R1a) has been demonstrated in rat and human testis, and ghrelin also affects testosterone (T) secretion in vitro, suggesting a role for this molecule in the direct control of testis function. However, whether this signaling system is present in pig testis, and the association with serum T remains largely unexplored. In this study we investigated the relationship between serum T levels and ghrelin and GHS-R1a gene expression in the testes of intact and immunocastrated boars. Testicular tissue and serum samples were collected from seven intact boars and seven recombinant GnRH-I immunocastrated boars. GHS-R1a gene expression in the testis was higher in immunocastrated than intact boars (2.22 ± 0.71 vs. 0.53 ± 0.23; P<0.01). Mean serum T levels were markedly lower in immunocastrated than intact boars (0.40 ± 0.04 vs. 2.10 ± 0.94 ng/mL, P<0.01). Ghrelin gene expression in testis did not differ between both groups of boars. GHS-R1a gene expression was positively correlated with ghrelin gene expression (r = 0.68, P<0.001), but negatively correlated with serum T concentrations (r = -0.83, P<0.001). Overall, the existence of ghrelin and GHS-R1a gene expression in pig testis, and the increase in GHS-R1a gene expression in the testes and the inverse correlation with serum T in immunocastrated boars are highly suggestive of a role for ghrelin in the regulation of mammalian testicular function.
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Affiliation(s)
- Fugui Fang
- Department of Animal Veterinary Science, College of Animal Science and Technology, Anhui Agricultural University, Hefei, PR China
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Garcia-Garcia RM. Integrative control of energy balance and reproduction in females. ISRN VETERINARY SCIENCE 2012; 2012:121389. [PMID: 23762577 PMCID: PMC3671732 DOI: 10.5402/2012/121389] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 09/04/2012] [Indexed: 11/23/2022]
Abstract
There is a strong association between nutrition and reproduction. Chronic dietary energy deficits as well as energy surpluses can impair reproductive capacity. Metabolic status impacts reproductive function at systemic level, modulating the hypothalamic GnRH neuronal network and/or the pituitary gonadotropin secretion through several hormones and neuropeptides, and at the ovarian level, acting through the regulation of follicle growth and steroidogenesis by means of the growth hormone-IGF-insulin system and local ovarian mediators. In the past years, several hormones and neuropeptides have been emerging as important mediators between energy balance and reproduction. The present review goes over the main sites implicated in the control of energy balance linked to reproductive success and summarizes the most important metabolic and neuroendocrine signals that participate in reproductive events with special emphasis on the role of recently discovered neuroendocrine peptides. Also, a little overview about the effects of maternal nutrition, affecting offspring reproduction, has been presented.
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Affiliation(s)
- R M Garcia-Garcia
- Physiology Department (Animal Physiology), Complutense University, Avenida Puerta de Hierro S/N, 28040 Madrid, Spain
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Food restriction, ghrelin, its antagonist and obestatin control expression of ghrelin and its receptor in chicken hypothalamus and ovary. Comp Biochem Physiol A Mol Integr Physiol 2012; 164:141-53. [PMID: 22877785 DOI: 10.1016/j.cbpa.2012.07.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/23/2012] [Accepted: 07/25/2012] [Indexed: 12/29/2022]
Abstract
The purpose of the present study was to identify the role of age, nutritional state and some metabolic hormones in control of avian hypothalamic and ovarian ghrelin/ghrelin receptor system. We examined the effect of food restriction, administration of ghrelin 1-18, ghrelin antagonistic analogue (D-Lys-3)-GHRP-6, obestatin and combinations of them on the expression of ghrelin and ghrelin receptor (GHS-R1a) in hypothalamus and ovary of old (23months of age) and young (7months of age) chickens. Expression of mRNAs for ghrelin and GHS-R1a in both hypothalamus and largest ovarian follicle was measured by RT-PCR. It was observed that food restriction could promote the expression of ghrelin and GHS-R1a in hypothalamus and ovary of the old chickens, but in the young chickens it reduced expression of ghrelin and did not affect expression of GHS-R1a in the ovary. Administration of ghrelin 1-18 did not affect hypothalamic or ovarian ghrelin mRNA, but significantly increased the expression of GHS-R1a in hypothalamus, but not in ovary. (D-Lys-3)-GHRP-6, significantly stimulated accumulation of ghrelin, but not GHS-R1a mRNA in hypothalamus or ghrelin or GHS-R1a in the ovary. Ghrelin 1-18 and (D-Lys-3)-GHRP-6, when given together, were able either to prevent or to induce effect of these hormones. Obestatin administration increased expression of ghrelin gene in the hypothalamus, but not expression of hypothalamic GHS-R1a, ovarian ghrelin and GHS-R1a. Furthermore, obestatin was able to modify effect of both ghrelin and fasting on hypothalamic and ovarian mRNA for ghrelin GHS-R1a. Our results (1) confirm the existence of ghrelin and its functional receptors GHS-R1a in the chicken hypothalamus and ovary (2) confirm the age-dependent control of ovarian ghrelin by feeding, (3) demonstrate, that nutritional status can influence the expression of both ghrelin and GHS-R1a in hypothalamus and in the ovary (3) demonstrates for the first time, that ghrelin can promote generation of its functional receptor in the hypothalamus, but not in the ovary, (4) show that ghrelin1-18 and (D-Lys-3)-GHRP-6 could not only be antagonists in the action on chicken hypothalamus and ovaries, but also independent regulators and even agonists, and (5) provide first evidence for action of obestatin on hypothalamic ghrelin and on the response of hypothalamic and ovarian ghrelin/GHS-R1a system to food restriction. These data indicate the involvement of both hypothalamic and ovarian ghrelin/GHS-R1 systems in mediating the effects of nutritional status, ghrelin and obestatin on reproductive processes.
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Słupecka M, Woliński J, Pierzynowski SG. The effects of enteral ghrelin administration on the remodeling of the small intestinal mucosa in neonatal piglets. ACTA ACUST UNITED AC 2012; 174:38-45. [DOI: 10.1016/j.regpep.2011.11.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 10/06/2011] [Accepted: 11/10/2011] [Indexed: 10/14/2022]
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Abstract
Ghrelin is the only potent orexigenic peptide in circulation. It stimulates food intake and leads to positive energy balance, adipogenesis, and body weight gain. However, the physiological significance of ghrelin in the regulation of energy homeostasis is controversial, since loss of ghrelin function in rodents does not necessarily lead to anorexia and weight loss. In this chapter, we discuss the metabolic function of ghrelin and are highlighting recent findings including the discovery and function of ghrelin-acylating enzyme ghrelin O-acyltransferase (GOAT). Based on available published data, we conclude that ghrelin is a principally important endogenous regulator of energy balance, which however may affect both food intake and systemic metabolism via independent mechanisms. Importantly, ghrelin, when acylated by GOAT, might represent a key molecular link between the sensing of consumed calories and the neuroendocrine control of energy homeostasis. Thus, agents antagonizing the action of ghrelin may have therapeutic potential in the therapy of obesity.
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Muccioli G, Lorenzi T, Lorenzi M, Ghè C, Arnoletti E, Raso GM, Castellucci M, Gualillo O, Meli R. Beyond the metabolic role of ghrelin: a new player in the regulation of reproductive function. Peptides 2011; 32:2514-21. [PMID: 22074955 DOI: 10.1016/j.peptides.2011.10.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 10/23/2011] [Accepted: 10/23/2011] [Indexed: 11/30/2022]
Abstract
Ghrelin is a gastric peptide, discovered by Kojima et al. (1999) [55] as a result of the search for an endogenous ligand interacting with the "orphan receptor" GHS-R1a (growth hormone secretagogue receptor type 1a). Ghrelin is composed of 28 aminoacids and is produced mostly by specific cells of the stomach, by the hypothalamus and hypophysis, even if its presence, as well as that of its receptors, has been demonstrated in many other tissues, not least in gonads. Ghrelin potently stimulates GH release and participates in the regulation of energy homeostasis, increasing food intake, decreasing energy output and exerting a lipogenetic effect. Furthermore, ghrelin influences the secretion and motility of the gastrointestinal tract, especially of the stomach, and, above all, profoundly affects pancreatic functions. Despite of these previously envisaged activities, it has recently been hypothesized that ghrelin regulates several aspects of reproductive physiology and pathology. In conclusion, ghrelin not only cooperates with other neuroendocrine factors, such as leptin, in the modulation of energy homeostasis, but also has a crucial role in the regulation of the hypothalamic-pituitary gonadal axis. In the current review we summarize the main targets of this gastric peptide, especially focusing on the reproductive system.
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Affiliation(s)
- Giampiero Muccioli
- Department of Drug Science and Technology, Division of Medical Pharmacology, University of Torino, Via P. Giuria 13, 10125 Torino, Italy
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Taché Y, Stengel A, Vaudry H. Editorial: As the field of ghrelin is moving forward toward translational applications, expert reviews on the multiple ghrelin actions may provide a broader overview of the relevance of this peptide as well as pointing toward research gaps to be filled. Peptides 2011; 32:2151-2. [PMID: 22024141 DOI: 10.1016/j.peptides.2011.10.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Sirotkin AV, Meszarošová M, Grossmann R, Benčo A, Valenzuela F. Effect of inhibitor and activator of ghrelin receptor (GHS-R1a) on porcine ovarian granulosa cell functions. Gen Comp Endocrinol 2011; 173:105-10. [PMID: 21600209 DOI: 10.1016/j.ygcen.2011.05.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 05/01/2011] [Accepted: 05/02/2011] [Indexed: 02/07/2023]
Abstract
It was previously shown, that ghrelin and its agonistic analogue, ghrelin 1-18, can be a stimulator of ovarian cell functions (promoter of proliferation, inhibitor of apoptosis and stimulator of hormones release). The aim of our studies was to compare the action of two ghrelin analogues - ghrelin 1-18, activator of ghrelin receptors (GHS-R1a), and (D-Lys3)-GHRP-6, its inhibitor, on porcine ovarian granulosa cell functions. Effects of (D-Lys3)-GHRP-6 added at doses of 0, 1, 10 or 100 ng/ml on the expression of markers of proliferation (PCNA, cyclin B1, MAPK/ERK1,2), apoptosis (bax, p53, caspase 3) and release of steroid hormones (progesterone, testosterone, estradiol) were examined. In addition, some effect of ghrelin 1-8 on some of these parameters (expression of MAPK/ERK1,2, bax, p53) were verified. It was shown, that (D-Lys3)-GHRP-6 promotes all markers of granulosa cell proliferation, inhibits all markers of apoptosis and stimulates the release of all three steroid hormones. Similar effects of (D-Lys3)-GHRP-6 (inhibitor of GHS-R1a) and ghrelin 1-18 (its stimulator) suggest that the examined effects of these substances on porcine ovaries are not mediated by GHS-R1a. Both chemical analogues could be potentially useful for stimulation of reproductive processes, at least in in vitro conditions.
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Affiliation(s)
- Alexander V Sirotkin
- Institute of Genetics and Reproduction, Animal Production Research Centre Nitra, 951 41 Lužianky near Nitra, Slovakia.
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Repaci A, Gambineri A, Pagotto U, Pasquali R. Ghrelin and reproductive disorders. Mol Cell Endocrinol 2011; 340:70-9. [PMID: 21453749 DOI: 10.1016/j.mce.2011.02.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 02/26/2011] [Accepted: 02/26/2011] [Indexed: 12/13/2022]
Abstract
Ghrelin is an important factor involved in most of the metabolic and hormonal signals which adapt the reproductive functions in conditions of altered energy balance. Moreover, the coordinated role of leptin and ghrelin appears in fact to have a specific role in the regulation of puberty. Systemic action of ghrelin on the reproductive axis involves the control of the hypothalamic-pituitary-gondal axis. In addition, it has been shown that ghrelin may directly act at a gonadal level in both females and males. Available data also demonstrate that sex steroid hormones and gonadotropins may in turn regulate the gonadal effect of ghrelin, as documented by studies performed in females with the polycystic ovary syndrome and in hypogonadal men. Notably, recent studies also confirm a potentially important role for ghrelin in fetal and neonatal energy balance, and specifically in allowing fetal adaptation to an adverse intrauterine environment.
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Affiliation(s)
- Andrea Repaci
- St. Orsola-Malpighi Hospital, University Alma Mater Studiorum, Bologna, Italy
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Roa J, García-Galiano D, Castellano JM, Gaytan F, Pinilla L, Tena-Sempere M. Metabolic control of puberty onset: new players, new mechanisms. Mol Cell Endocrinol 2010; 324:87-94. [PMID: 20026241 DOI: 10.1016/j.mce.2009.12.018] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 12/11/2009] [Accepted: 12/11/2009] [Indexed: 01/22/2023]
Abstract
Puberty, as the end-point of a complex series of maturational events affecting the components of the hypothalamic-pituitary-gonadal (HPG) axis, is gated by the state of body energy reserves and sensitive to different metabolic cues; conditions of severe metabolic stress and energy unbalance (from anorexia to morbid obesity) being commonly linked to perturbation of the onset of puberty. In the last two decades, the neuroendocrine mechanisms responsible for the tight coupling between energy homeostasis and puberty onset have begun to be deciphered. These seemingly involve a plethora of metabolic hormones and neuropeptides, which impinge and integrate (mostly) at the hypothalamic centers governing reproduction. Yet, characterization of the mechanisms of action of such regulators (and even their nature and physiological relevance) still remains incomplete. In this review, we will summarize some recent developments in our knowledge of the effects and mechanisms of action of two key metabolic hormones, leptin and ghrelin, in the control of puberty onset. In addition, the roles of the hypothalamic Kiss1 system in the metabolic gating of puberty will be reviewed, with special attention to its regulation by leptin and the recent identification of the putative roles of Crtc1 and mTOR signaling as molecular conduits for the metabolic control of Kiss1 expression. Elucidation of these novel players and regulatory mechanisms will help for a better understanding of the determinants of the timing of puberty, and its eventual alterations in adverse metabolic conditions.
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Affiliation(s)
- Juan Roa
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, Córdoba, Spain
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Martos-Moreno GA, Chowen JA, Argente J. Metabolic signals in human puberty: effects of over and undernutrition. Mol Cell Endocrinol 2010; 324:70-81. [PMID: 20026379 DOI: 10.1016/j.mce.2009.12.017] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 12/08/2009] [Accepted: 12/11/2009] [Indexed: 01/19/2023]
Abstract
Puberty in mammals is associated with important physical and psychological changes due to the increase in sex steroids and growth hormone (GH). Indeed, an increase in growth velocity and the attainment of sexual maturity for future reproductive function are the hallmark changes during this stage of life. Both growth and reproduction consume high levels of energy, requiring suitable energy stores to face these physiological functions. During the last two decades our knowledge concerning how peptides produced in the digestive tract (in charge of energy intake) and in adipose tissue (in charge of energy storage) provide information regarding metabolic status to the central nervous system (CNS) has increased dramatically. Moreover, these peptides have been shown to play an important role in modulating the gonadotropic axis with their absence or an imbalance in their secretion being able to disturb pubertal onset or progression. In this article we will review the current knowledge concerning the role played by leptin, the key adipokine in energy homeostasis, and ghrelin, the only orexigenic and growth-promoting peptide produced by the digestive tract, on sexual development. The normal evolutionary pattern of these peripherally produced metabolic signals throughout human puberty will be summarized. The effect of two opposite situations of chronic malnutrition, obesity and anorexia, on these signals and how they influence the course of puberty will also be discussed. Finally, we will briefly mention other peptides derived from the digestive tract (such as PYY) that may be involved in the regulatory link between energy homeostasis and sexual development.
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Affiliation(s)
- G A Martos-Moreno
- Hospital Infantil Universitario Niño Jesús, Department of Endocrinology, Universidad Autónoma de Madrid, Madrid, Spain
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Veldhuis JD, Bowers CY. Integrating GHS into the Ghrelin System. INTERNATIONAL JOURNAL OF PEPTIDES 2010; 2010:879503. [PMID: 20798846 PMCID: PMC2925380 DOI: 10.1155/2010/879503] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 12/30/2009] [Indexed: 12/21/2022]
Abstract
Oligopeptide derivatives of metenkephalin were found to stimulate growth-hormone (GH) release directly by pituitary somatotrope cells in vitro in 1977. Members of this class of peptides and nonpeptidyl mimetics are referred to as GH secretagogues (GHSs). A specific guanosine triphosphatate-binding protein-associated heptahelical transmembrane receptor for GHS was cloned in 1996. An endogenous ligand for the GHS receptor, acylghrelin, was identified in 1999. Expression of ghrelin and homonymous receptor occurs in the brain, pituitary gland, stomach, endothelium/vascular smooth muscle, pancreas, placenta, intestine, heart, bone, and other tissues. Principal actions of this peptidergic system include stimulation of GH release via combined hypothalamopituitary mechanisms, orexigenesis (appetitive enhancement), insulinostasis (inhibition of insulin secretion), cardiovascular effects (decreased mean arterial pressure and vasodilation), stimulation of gastric motility and acid secretion, adipogenesis with repression of fat oxidation, and antiapoptosis (antagonism of endothelial, neuronal, and cardiomyocyte death). The array of known and proposed interactions of ghrelin with key metabolic signals makes ghrelin and its receptor prime targets for drug development.
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Affiliation(s)
- Johannes D. Veldhuis
- Department of Medicine, Endocrine Research Unit, Mayo School of Graduate Medical Education, Clinical Translational Science Center, Mayo Clinic, Rochester, MN 55905, USA
| | - Cyril Y. Bowers
- Division of Endocrinology, Department of Internal Medicine, Tulane University Health Sciences Center, New Orleans, LA 70112, USA
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48
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Shah SN, Nyby JG. Ghrelin's quick inhibition of androgen-dependent behaviors of male house mice (Mus musculus). Horm Behav 2010; 57:291-6. [PMID: 20044999 DOI: 10.1016/j.yhbeh.2009.12.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Revised: 12/17/2009] [Accepted: 12/21/2009] [Indexed: 11/16/2022]
Abstract
Ghrelin is a peptide hormone released by the stomach that stimulates hunger. Ghrelin also suppresses reproductive physiology by inhibiting the HPG axis. However, to our knowledge, our results are the first to demonstrate ghrelin's quick suppression of sex-hormone-regulated behaviors. In experiment 1, 2 orexigenic i.p. ghrelin injections (0.165 mg/kg and 0.33 mg/kg) suppressed male courtship behavior (ultrasonic calling to a female) and intermale aggression (latency to attack a stimulus male) 20 min following administration. Experiment 2 (examining only the 0.33 mg/kg dose ) replicated ghrelin's suppression of ultrasonic calling and intermale aggression; however, a third behavior, preference for volatile female odors (20 min following administration), was not significantly inhibited. In experiment 2, ghrelin treatment did not affect general locomotor activity (distance traveled 20 min following injection) or seminal vesicle weight (measured 5 days after completing ghrelin injections). We hypothesize that ghrelin's quick suppression of male aggression and ultrasonic mating calls was mediated through its effects on the brain (rather than indirectly through inhibition of the HPG axis).
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Affiliation(s)
- Sara N Shah
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
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Osterstock G, Escobar P, Mitutsova V, Gouty-Colomer LA, Fontanaud P, Molino F, Fehrentz JA, Carmignac D, Martinez J, Guerineau NC, Robinson ICAF, Mollard P, Méry PF. Ghrelin stimulation of growth hormone-releasing hormone neurons is direct in the arcuate nucleus. PLoS One 2010; 5:e9159. [PMID: 20161791 PMCID: PMC2820089 DOI: 10.1371/journal.pone.0009159] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Accepted: 01/08/2010] [Indexed: 11/26/2022] Open
Abstract
Background Ghrelin targets the arcuate nucleus, from where growth hormone releasing hormone (GHRH) neurones trigger GH secretion. This hypothalamic nucleus also contains neuropeptide Y (NPY) neurons which play a master role in the effect of ghrelin on feeding. Interestingly, connections between NPY and GHRH neurons have been reported, leading to the hypothesis that the GH axis and the feeding circuits might be co-regulated by ghrelin. Principal Findings Here, we show that ghrelin stimulates the firing rate of identified GHRH neurons, in transgenic GHRH-GFP mice. This stimulation is prevented by growth hormone secretagogue receptor-1 antagonism as well as by U-73122, a phospholipase C inhibitor and by calcium channels blockers. The effect of ghrelin does not require synaptic transmission, as it is not antagonized by γ-aminobutyric acid, glutamate and NPY receptor antagonists. In addition, this hypothalamic effect of ghrelin is independent of somatostatin, the inhibitor of the GH axis, since it is also found in somatostatin knockout mice. Indeed, ghrelin does not modify synaptic currents of GHRH neurons. However, ghrelin exerts a strong and direct depolarizing effect on GHRH neurons, which supports their increased firing rate. Conclusion Thus, GHRH neurons are a specific target for ghrelin within the brain, and not activated secondary to altered activity in feeding circuits. These results support the view that ghrelin related therapeutic approaches could be directed separately towards GH deficiency or feeding disorders.
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Affiliation(s)
- Guillaume Osterstock
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Pauline Escobar
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Violeta Mitutsova
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Laurie-Anne Gouty-Colomer
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Pierre Fontanaud
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - François Molino
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Jean-Alain Fehrentz
- Université Montpellier 1, 2, Montpellier, France
- CNRS UMR 5247, Institut des Biomolécules Max Mousseron, Montpellier, France
| | - Danielle Carmignac
- Division of Molecular Neuroendocrinology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Jean Martinez
- Université Montpellier 1, 2, Montpellier, France
- CNRS UMR 5247, Institut des Biomolécules Max Mousseron, Montpellier, France
| | - Nathalie C. Guerineau
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Iain C. A. F. Robinson
- Division of Molecular Neuroendocrinology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Patrice Mollard
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
| | - Pierre-François Méry
- Inserm U-661, Montpellier, France
- CNRS UMR 5203, Institut de Génomique Fonctionnelle, Montpellier, France
- Université Montpellier 1, 2, Montpellier, France
- * E-mail:
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Du C, Li H, Cao G, Xilingaowa, Wang C, Li C. Expression of the Orexigenic Peptide Ghrelin and the Type 1a Growth Hormone Secretagogue Receptor in Sheep Oocytes and Pre-implantation Embryos ProducedIn Vitro. Reprod Domest Anim 2010; 45:92-8. [DOI: 10.1111/j.1439-0531.2008.01259.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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