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Golshan M, Alavi SMH, Hatef A, Kazori N, Socha M, Milla S, Sokołowska-Mikołajczyk M, Unniappan S, Butts IAE, Linhart O. Impact of absolute food deprivation on the reproductive system in male goldfish exposed to sex steroids. J Comp Physiol B 2024; 194:411-426. [PMID: 38880793 DOI: 10.1007/s00360-024-01570-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 01/18/2024] [Accepted: 06/05/2024] [Indexed: 06/18/2024]
Abstract
There is a link between metabolism and reproduction as metabolic hormones affect hypothalamus-pituitary-testis (HPT) hormonal functions and vice versa. The aim of the present study was to investigate the effects of negative energy balance on the reproductive system in male goldfish exposed to testosterone (T) and 17β-estradiol (E2). Following 7 days of food deprivation (FD), ANOVA models showed significant FD × sex steroid interactions on sperm quality and circulating sex steroid levels. When FD effects were investigated, 11-ketotestosterone (11-KT) level and sperm motility and velocity decreased in food-deprived goldfish in the control group. In E2-exposed goldfish, FD decreased sperm production in addition to sperm motility and velocity that coincided with an elevation of circulating E2 level. However, FD did not significantly impact sex steroids and sperm quality in T-exposed goldfish. ANOVA models showed non-significant FD × sex steroid interactions for HSI, GSI, circulating luteinizing hormone (Lh) level, and metabolic (preproghrelin, goat and nucb2) and reproductive (kiss1, gpr54 and gnrh3) mRNAs. Furthermore, results showed that FD decreased HSI, and increased Lh levels and testicular preproghrelin and goat mRNAs, while sex steroids increased mid-brain nucb2, kiss1 and gpr54 mRNAs. Together, our results suggest that FD-induced inhibition of androgenesis resulted in diminished sperm quality associated with activation of the testicular ghrelinergic system, and negative feedback of 11-KT increased Lh level. The FD-induced testicular metabolic and hormonal system was impacted in goldfish exposed to sex steroids. However, the negative effects of FD on sperm quality were accelerated in E2-exposed goldfish due to estrogenic activity. This study provides novel information to better understand metabolic-associated reproductive disorders in fish.
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Affiliation(s)
- Mahdi Golshan
- Iranian Fisheries Science Research Institute, Agricultural Research, Education and Extension Organization, Tehran, Iran
| | - Sayyed Mohammad Hadi Alavi
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, Vodňany, Czech Republic.
- School of Biology, College of Science, University of Tehran, Tehran, Iran.
| | - Azadeh Hatef
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B4, Canada
- Toxicology Centre, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B3, Canada
| | - Negar Kazori
- School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Magdalena Socha
- Faculty of Animal Science, University of Agriculture in Kraków, Kraków, Poland
| | - Sylvain Milla
- Research Unit Animal and Functionalities of Animal Products, INRA, University of Lorraine, Vandoeuvre-lès-Nancy, France
| | | | - Suraj Unniappan
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5B4, Canada
| | - Ian A E Butts
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Otomar Linhart
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in České Budějovice, Vodňany, Czech Republic
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2
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Jafari-Gharabaghlou D, Vaghari-Tabari M, Oghbaei H, Lotz L, Zarezadeh R, Rastgar Rezaei Y, Ranjkesh M, Nouri M, Fattahi A, Nikanfar S, Dittrich R. Role of adipokines in embryo implantation. Endocr Connect 2021; 10:R267-R278. [PMID: 34559064 PMCID: PMC8558901 DOI: 10.1530/ec-21-0288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 09/24/2021] [Indexed: 11/08/2022]
Abstract
Embryo implantation is a complex process in which multiple molecules acting together under strict regulation. Studies showed the production of various adipokines and their receptors in the embryo and uterus, where they can influence the maternal-fetal transmission of metabolites and embryo implantation. Therefore, these cytokines have opened a novel area of study in the field of embryo-maternal crosstalk during early pregnancy. In this respect, the involvement of adipokines has been widely reported in the regulation of both physiological and pathological aspects of the implantation process. However, the information about the role of some recently identified adipokines is limited. This review aims to highlight the role of various adipokines in embryo-maternal interactions, endometrial receptivity, and embryo implantation, as well as the underlying molecular mechanisms.
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Affiliation(s)
- Davoud Jafari-Gharabaghlou
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mostafa Vaghari-Tabari
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hajar Oghbaei
- Department of Physiology, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Laura Lotz
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen–Nürnberg, Erlangen, Germany
| | - Reza Zarezadeh
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yeganeh Rastgar Rezaei
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahnaz Ranjkesh
- Medical Radiation Science Research Group (MRSRG), Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Nouri
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Fattahi
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen–Nürnberg, Erlangen, Germany
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Correspondence should be addressed to A Fattahi or S Nikanfar: or
| | - Saba Nikanfar
- Department of Clinical Biochemistry and Laboratory Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
- Correspondence should be addressed to A Fattahi or S Nikanfar: or
| | - Ralf Dittrich
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen–Nürnberg, Erlangen, Germany
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3
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The Role of the Gastric Hormones Ghrelin and Nesfatin-1 in Reproduction. Int J Mol Sci 2021. [DOI: 10.3390/ijms222011059
expr 982648605 + 846360072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Ghrelin and nesfatin-1 are enteroendocrine peptide hormones expressed in rat X/A-like and human P/D1cells of the gastric mucosa. Besides their effect on food intake, both peptides are also implicated in various other physiological systems. One of these is the reproductive system. This present review illustrates the distribution of ghrelin and nesfatin-1 along the hypothalamus–pituitary–gonadal (HPG) axis, their modulation by reproductive hormones, and effects on reproductive functions as well as highlighting gaps in current knowledge to foster further research.
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4
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The Role of the Gastric Hormones Ghrelin and Nesfatin-1 in Reproduction. Int J Mol Sci 2021; 22:11059. [PMID: 34681721 PMCID: PMC8539660 DOI: 10.3390/ijms222011059&set/a 934136356+984013925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Ghrelin and nesfatin-1 are enteroendocrine peptide hormones expressed in rat X/A-like and human P/D1cells of the gastric mucosa. Besides their effect on food intake, both peptides are also implicated in various other physiological systems. One of these is the reproductive system. This present review illustrates the distribution of ghrelin and nesfatin-1 along the hypothalamus-pituitary-gonadal (HPG) axis, their modulation by reproductive hormones, and effects on reproductive functions as well as highlighting gaps in current knowledge to foster further research.
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5
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Schalla MA, Stengel A. The Role of the Gastric Hormones Ghrelin and Nesfatin-1 in Reproduction. Int J Mol Sci 2021; 22:ijms222011059. [PMID: 34681721 PMCID: PMC8539660 DOI: 10.3390/ijms222011059] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/11/2022] Open
Abstract
Ghrelin and nesfatin-1 are enteroendocrine peptide hormones expressed in rat X/A-like and human P/D1cells of the gastric mucosa. Besides their effect on food intake, both peptides are also implicated in various other physiological systems. One of these is the reproductive system. This present review illustrates the distribution of ghrelin and nesfatin-1 along the hypothalamus–pituitary–gonadal (HPG) axis, their modulation by reproductive hormones, and effects on reproductive functions as well as highlighting gaps in current knowledge to foster further research.
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Affiliation(s)
- Martha A. Schalla
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Berlin Institute of Health, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, 12203 Berlin, Germany;
| | - Andreas Stengel
- Charité Center for Internal Medicine and Dermatology, Department for Psychosomatic Medicine, Berlin Institute of Health, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, 12203 Berlin, Germany;
- Department of Psychosomatic Medicine and Psychotherapy, Medical University Hospital Tübingen, 72076 Tübingen, Germany
- Correspondence:
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6
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Nikanfar S, Oghbaei H, Rastgar Rezaei Y, Zarezadeh R, Jafari-Gharabaghlou D, Nejabati HR, Bahrami Z, Bleisinger N, Samadi N, Fattahi A, Nouri M, Dittrich R. Role of adipokines in the ovarian function: Oogenesis and steroidogenesis. J Steroid Biochem Mol Biol 2021; 209:105852. [PMID: 33610800 DOI: 10.1016/j.jsbmb.2021.105852] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/28/2020] [Accepted: 01/30/2021] [Indexed: 01/02/2023]
Abstract
Adipokines are mainly produced by adipose tissue; however, their expression has been reported in other organs including female reproductive tissues. Therefore, adipokines have opened new avenues of research in female fertility. In this regard, studies reported different roles for certain adipokines in ovarian function, although the role of other recently identified adipokines is still controversial. It seems that adipokines are essential for normal ovarian function and their abnormal levels could be associated with ovarian-related disorders. The objective of this study is to review the available information regarding the role of adipokines in ovarian functions including follicular development, oogenesis and steroidogenesis and also their involvement in ovary-related disorders.
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Affiliation(s)
- Saba Nikanfar
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hajar Oghbaei
- Department of Physiology, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Yeganeh Rastgar Rezaei
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran; Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Zarezadeh
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Davoud Jafari-Gharabaghlou
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Reza Nejabati
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zahra Bahrami
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Nathalie Bleisinger
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen, Nürnberg, Erlangen, Germany
| | - Naser Samadi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Fattahi
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen, Nürnberg, Erlangen, Germany; Women's Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Mohammad Nouri
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Ralf Dittrich
- Department of Obstetrics and Gynecology, Erlangen University Hospital, Friedrich-Alexander University of Erlangen, Nürnberg, Erlangen, Germany
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Stroh MA, Winter MK, McCarson KE, Thyfault JP, Zhu H. NCB5OR Deficiency in the Cerebellum and Midbrain Leads to Dehydration and Alterations in Thirst Response, Fasted Feeding Behavior, and Voluntary Exercise in Mice. THE CEREBELLUM 2019; 17:152-164. [PMID: 28887630 DOI: 10.1007/s12311-017-0880-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cytosolic NADH-cytochrome-b5-oxidoreductase (NCB5OR) is ubiquitously expressed in animal tissues. We have previously reported that global ablation of NCB5OR in mice results in early-onset lean diabetes with decreased serum leptin levels and increased metabolic and feeding activities. The conditional deletion of NCB5OR in the mouse cerebellum and midbrain (conditional knock out, CKO mice) results in local iron dyshomeostasis and altered locomotor activity. It has been established that lesion to or removal of the cerebellum leads to changes in nutrient organization, visceral response, feeding behavior, and body weight. This study assessed whether loss of NCB5OR in the cerebellum and midbrain altered feeding or metabolic activity and had an effect on serum T3, cortisol, prolactin, and leptin levels. Metabolic cage data revealed that 16 week old male CKO mice had elevated respiratory quotients and decreased respiratory water expulsion, decreased voluntary exercise, and altered feeding and drinking behavior compared to wild-type littermate controls. Most notably, male CKO mice displayed higher consumption of food during refeeding after a 48-h fast. Echo MRI revealed normal body composition but decreased total water content and hydration ratios in CKO mice. Increased serum osmolality measurements confirmed the dehydration status of male CKO mice. Serum leptin levels were significantly elevated in male CKO mice while prolactin, T3, and cortisol levels remain unchanged relative to wild-type controls, consistent with elevated transcript levels for leptin receptors (short form) in the male CKO mouse cerebellum. Taken together, these findings suggest altered feeding response post starvation as a result of NCB5OR deficiency in the cerebellum.
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Affiliation(s)
- Matthew A Stroh
- Landon Center on Aging, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Neuroscience Graduate Program, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Neurology, Washington University in St. Louis School of Medicine, St. Louis, MO, 63110, USA
| | - Michelle K Winter
- Kansas Intellectual and Developmental Disabilities Research Center, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Kenneth E McCarson
- Kansas Intellectual and Developmental Disabilities Research Center, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - John P Thyfault
- Department of Molecular Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, 66160, USA.,Research Service, Kansas City VA Medical Center, Kansas City, MO, 64128, USA
| | - Hao Zhu
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS, 66160, USA. .,Neuroscience Graduate Program, University of Kansas Medical Center, Kansas City, KS, 66160, USA. .,Department of Clinical Laboratory Sciences, University of Kansas Medical Center, 3901 Rainbow Blvd., MSN 4048G-Eaton, Kansas City, KS, 66160, USA.
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8
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Leptin regulates neuropeptides associated with food intake and GnRH secretion. ANNALES D'ENDOCRINOLOGIE 2019; 80:38-46. [DOI: 10.1016/j.ando.2018.07.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 05/31/2018] [Accepted: 07/26/2018] [Indexed: 12/18/2022]
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9
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Insights into leptin signaling and male reproductive health: the missing link between overweight and subfertility? Biochem J 2018; 475:3535-3560. [DOI: 10.1042/bcj20180631] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 09/28/2018] [Accepted: 10/19/2018] [Indexed: 12/24/2022]
Abstract
Obesity stands as one of the greatest healthcare challenges of the 21st century. Obesity in reproductive-age men is ever more frequent and is reaching upsetting levels. At the same time, fertility has taken an inverse direction and is decreasing, leading to an increased demand for fertility treatments. In half of infertile couples, there is a male factor alone or combined with a female factor. Furthermore, male fertility parameters such as sperm count and concentration went on a downward spiral during the last few decades and are now approaching the minimum levels established to achieve successful fertilization. Hence, the hypothesis that obesity and deleterious effects in male reproductive health, as reflected in deterioration of sperm parameters, are somehow related is tempting. Most often, overweight and obese individuals present leptin levels directly proportional to the increased fat mass. Leptin, besides the well-described central hypothalamic effects, also acts in several peripheral organs, including the testes, thus highlighting a possible regulatory role in male reproductive function. In the last years, research focusing on leptin effects in male reproductive function has unveiled additional roles and molecular mechanisms of action for this hormone at the testicular level. Herein, we summarize the novel molecular signals linking metabolism and male reproductive function with a focus on leptin signaling, mitochondria and relevant pathways for the nutritional support of spermatogenesis.
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10
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Pouchain Ribeiro Neto R, Clarke IJ, Conductier G. Alteration in the relationship between tanycytes and gonadotrophin-releasing hormone neurosecretory terminals following long-term metabolic manipulation in the sheep. J Neuroendocrinol 2017; 29. [PMID: 28722251 DOI: 10.1111/jne.12509] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 12/30/2022]
Abstract
The activity of the hypothalamic-pituitary gonadal axis is influenced by energy reserves, such that an increase or a decrease in adiposity may perturb the secretion and action of gonadotrophin-releasing hormone (GnRH). This is considered to be a result of the signalling of hormones such as leptin, which act upon neuronal systems controlling GnRH secretion. Other work shows plasticity in the relationship between tanycytes and GnRH neurosecretory terminals in the median eminence across the oestrous cycle and we hypothesised that a similar plasticity may occur with altered metabolic status. We studied Lean, Normal and Fat ovariectomised ewes, which displayed differences in gonadotrophin status, and investigated the relationship between tanycytes and GnRH neuroterminals. Under both Lean and Fat conditions, an altered anatomical arrangement between these two elements was observed in the vicinity of the blood vessels of the primary plexus of the hypophysial portal blood system. These data suggest that such plasticity is an important determinant of the rate of secretion of GnRH in animals of differing metabolic status and that this also contributes to the relative hypogonadotrophic condition prevailing with metabolic extremes.
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Affiliation(s)
- R Pouchain Ribeiro Neto
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Neuroscience Program, Monash Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - I J Clarke
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Neuroscience Program, Monash Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - G Conductier
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
- Neuroscience Program, Monash Biomedicine Discovery Institute, Department of Physiology, Monash University, Melbourne, Victoria, Australia
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11
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Egecioglu E, Prieto‐Garcia L, Studer E, Westberg L, Jerlhag E. The role of ghrelin signalling for sexual behaviour in male mice. Addict Biol 2016; 21:348-59. [PMID: 25475101 DOI: 10.1111/adb.12202] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Ghrelin, a gut-brain signal, is well known to regulate energy homeostasis, food intake and appetite foremost via hypothalamic ghrelin receptors (GHS-R1A). In addition, ghrelin activates the reward systems in the brain, namely the mesolimbic dopamine system, and regulates thereby the rewarding properties of addictive drugs as well as of palatable foods. Given that the mesolimbic dopamine system mandates the reinforcing properties of addictive drugs and natural rewards, such as sexual behaviour, we hypothesize that ghrelin plays an important role for male sexual behaviour, a subject for the present studies. Herein we show that ghrelin treatment increases, whereas pharmacological suppression (using the GHSR-1A antagonist JMV2959) or genetic deletion of the GHS-R1A in male mice decreases the sexual motivation for as well as sexual behaviour with female mice in oestrus. Pre-treatment with L-dopa (a dopamine precursor) prior to treatment with JMV2959 significantly increased the preference for female mouse compared with vehicle treatment. On the contrary, treatment with 5-hydroxythyptohan (a precursor for serotonin) prior to treatment with JMV2959 decreased the sexual motivation compared to vehicle. In separate experiments, we show that ghrelin and GHS-R1A antagonism do not affect the time spent over female bedding as measured in the androgen-dependent bedding test. Collectively, these data show that the hunger hormone ghrelin and its receptor are required for normal sexual behaviour in male mice and that the effects of the ghrelin signalling system on sexual behaviour involve dopamine neurotransmission.
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Affiliation(s)
- Emil Egecioglu
- Department of Pharmacology Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Sweden
| | - Luna Prieto‐Garcia
- Department of Pharmacology Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Sweden
| | - Erik Studer
- Department of Pharmacology Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Sweden
| | - Lars Westberg
- Department of Pharmacology Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Sweden
| | - Elisabet Jerlhag
- Department of Pharmacology Institute of Neuroscience and Physiology The Sahlgrenska Academy at the University of Gothenburg Sweden
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12
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Ghrelin Actions on Somatotropic and Gonadotropic Function in Humans. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016; 138:3-25. [PMID: 26940384 DOI: 10.1016/bs.pmbts.2015.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ghrelin, a 28 amino-acid octanoylated peptide predominantly produced by the stomach, was discovered to be the natural ligand of the type 1a GH secretagogue receptor (GHS-R1a). It was thus considered as a natural GHS additional to GHRH, although later on ghrelin has mostly been considered a major orexigenic factor. The GH-releasing action of ghrelin takes place both directly on pituitary cells and through modulation of GHRH from the hypothalamus; some functional antisomatostatin action has also been shown. However, ghrelin is much more than a natural GH secretagogue. In fact, it also modulates lactotroph and corticotroph secretion in humans as well as in animals and plays a relevant role in the modulation of the hypothalamic-pituitary-gonadal function. Several studies have indicated that ghrelin plays an inhibitory effect on gonadotropin pulsatility, is involved in the regulation of puberty onset in animals, and may regulate spermatogenesis, follicular development and ovarian cell functions in humans. In this chapter ghrelin actions on the GH/IGF-I and the gonadal axes will be revised. The potential therapeutic role of ghrelin as a treatment of catabolic conditions will also be discussed.
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13
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Rato L, Alves MG, Cavaco JE, Oliveira PF. High-energy diets: a threat for male fertility? Obes Rev 2014; 15:996-1007. [PMID: 25346452 DOI: 10.1111/obr.12226] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 08/26/2014] [Accepted: 08/26/2014] [Indexed: 12/18/2022]
Abstract
Male fertility is declining in developed countries, as well as in developing countries. External factors linked to lifestyle, such as eating disorders, negatively affect spermatogenesis, both at central and gonadal levels. The overconsumption of high-energy diets (HED) alters the functioning of the male reproductive axis and consequently affects the testicular physiology, disrupting its metabolism and bioenergetic capacity. Testicular metabolism presents unique characteristics, partly because of its cellular heterogeneity and to the specific functions that each cell type plays within the testicular environment. Disruption of the tightly regulated metabolic pathways leads to adverse reproductive outcomes, such as inefficient energy supply to germ cells, sperm defects or spermatogenesis arrest. Testicular metabolic alterations induced by HED intake may also lead to mitochondrial dysfunction, which is closely associated to reactive oxygen species (ROS) overproduction and oxidative stress. ROS easily target spermatozoa DNA and lipids, contributing to decreased sperm quality. Thus, understanding the detrimental effects of HED overconsumption on the pathways underlying testicular metabolism and sperm production is imperative; otherwise, one may favour a transgenerational amplification of subfertility. Herein, we present an up-to-date overview of the effects of HED on testicular metabolism, sperm parameters and the subsequent consequences for male fertility.
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Affiliation(s)
- L Rato
- CICS - UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal
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14
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Delporte C. Structure and physiological actions of ghrelin. SCIENTIFICA 2013; 2013:518909. [PMID: 24381790 PMCID: PMC3863518 DOI: 10.1155/2013/518909] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/10/2013] [Indexed: 05/30/2023]
Abstract
Ghrelin is a gastric peptide hormone, discovered as being the endogenous ligand of growth hormone secretagogue receptor. Ghrelin is a 28 amino acid peptide presenting a unique n-octanoylation modification on its serine in position 3, catalyzed by ghrelin O-acyl transferase. Ghrelin is mainly produced by a subset of stomach cells and also by the hypothalamus, the pituitary, and other tissues. Transcriptional, translational, and posttranslational processes generate ghrelin and ghrelin-related peptides. Homo- and heterodimers of growth hormone secretagogue receptor, and as yet unidentified receptors, are assumed to mediate the biological effects of acyl ghrelin and desacyl ghrelin, respectively. Ghrelin exerts wide physiological actions throughout the body, including growth hormone secretion, appetite and food intake, gastric secretion and gastrointestinal motility, glucose homeostasis, cardiovascular functions, anti-inflammatory functions, reproductive functions, and bone formation. This review focuses on presenting the current understanding of ghrelin and growth hormone secretagogue receptor biology, as well as the main physiological effects of ghrelin.
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Affiliation(s)
- Christine Delporte
- Laboratory of Pathophysiological and Nutritional Biochemistry, Université Libre de Bruxelles, 808 Route de Lennik, Bat G/E-CP611, 1070 Brussels, Belgium
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15
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Steinman J, DeBoer MD. Treatment of cachexia: melanocortin and ghrelin interventions. VITAMINS AND HORMONES 2013; 92:197-242. [PMID: 23601426 DOI: 10.1016/b978-0-12-410473-0.00008-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cachexia is a condition typified by wasting of fat and LBM caused by anorexia and further endocrinological modulation of energy stores. Diseases known to cause cachectic symptoms include cancer, chronic kidney disease, and chronic heart failure; these conditions are associated with increased levels of proinflammatory cytokines and increased resting energy expenditure. Early studies have suggested the central melanocortin system as one of the main mediators of the symptoms of cachexia. Pharmacological and genetic antagonism of these pathways attenuates cachectic symptoms in laboratory models; effects have yet to be studied in humans. In addition, ghrelin, an endogenous orexigenic hormone with receptors on melanocortinergic neurons, has been shown to ameliorate symptoms of cachexia, at least in part, by an increase in appetite via melanocortin modulation, in addition to its anticatabolic and anti-inflammatory effects. These effects of ghrelin have been confirmed in multiple types of cachexia in both laboratory and human studies, suggesting a positive future for cachexia treatments.
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Affiliation(s)
- Jeremy Steinman
- Division of Pediatric Endocrinology, Department of Pediatrics, P.O. Box 800386, University of Virginia, Charlottesville, Virginia, USA
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16
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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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17
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Abstract
Prevalence of hypogonadism in men with cancer has been reported between 40% and 90%, which is significantly higher than in the general population. Hypogonadism is likely to affect the quality of life in these patients by contributing to non-specific symptoms, including decreased energy, anorexia, sarcopenia, weight loss, depression, insomnia, fatigue, weakness, and sexual dysfunction. Pathogenesis of hypogonadism in cancer patients is thought to be multi-factorial. Inflammation may play an important role, but leptin, opioids, ghrelin, and high-dose chemotherapy through different mechanisms have all been implicated as the cause. Hypogonadism is also associated with poor survival in cancer patients. Data looking into the treatment of hypogonadal male cancer patients with testosterone are limited. However, improvements in body weight, muscle strength, lean body mass, and quality of life have been shown in hypogonadal men with other chronic diseases on testosterone replacement therapy. Prospective and interventional trials are needed to test the efficacy and safety of testosterone treatment in improving quality of life of these patients.
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Affiliation(s)
- Basil O. Burney
- Division of Endocrinology, Diabetes and Metabolism, Michael E. DeBakey Veterans Affairs Medical Center, Baylor College of Medicine, 2002 Holcombe Blvd, Bldg 109, Rm 210, Houston, TX 77030 USA
| | - Jose M. Garcia
- Division of Endocrinology, Diabetes and Metabolism, Michael E. DeBakey Veterans Affairs Medical Center, Baylor College of Medicine, 2002 Holcombe Blvd, Bldg 109, Rm 210, Houston, TX 77030 USA
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18
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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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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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20
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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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21
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Xiang L, He G. Caloric restriction and antiaging effects. ANNALS OF NUTRITION AND METABOLISM 2011; 58:42-8. [PMID: 21304246 DOI: 10.1159/000323748] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Accepted: 12/16/2010] [Indexed: 12/30/2022]
Abstract
Caloric restriction (CR) is widely used to study aging processes. It is a simple and highly reproducible method for delaying the aging process, preventing the onset of aging-related diseases and extending average or maximum lifespan. However, the mechanism underlying these effects of CR is still not clear. CR can inhibit growth, reduce body size and maintain a low body temperature. At the same time, there is a measurable decrease in the volume of adipose tissue, hyperglycemia and hyperinsulinemia, accompanied by modifications of lipid and energy metabolism and increased resistance to endogenous and extraneous stress. The metabolic changes induced by dietary restriction, the inhibition of fat deposition in nonadipose tissue and the effects on signal transduction are considered the most likely candidates for mechanisms underlying the effects of CR.
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Affiliation(s)
- Lan Xiang
- School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
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22
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Izzo G, Ferrara D, Napolitano F, Crispo AA, d'Istria M, Aniello F, Minucci S. Identification of a cDNA encoding for Ghrelin in the testis of the frog Pelophylax esculentus and its involvement in spermatogenesis. Comp Biochem Physiol A Mol Integr Physiol 2010; 158:367-73. [PMID: 20849974 DOI: 10.1016/j.cbpa.2010.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 09/08/2010] [Accepted: 09/09/2010] [Indexed: 10/19/2022]
Abstract
GHRELIN (GHRL) is an acylated peptide that contains 28-amino acids prevalently expressed in the stomach of several species. Specifically, it contributes to energy balance, but some new evidence highlights its role in the regulation of reproductive functions. In fact, this protein has been detected at testicular level in the tubular and interstitial compartments of several vertebrate species, and previous research has demonstrated that GHRL affects various aspects of spermatogenesis and steroidogenesis. GHRL clearly plays an inhibitory role in mammalian reproduction, in contrast GHRL stimulates reproductive functions in non mammalian vertebrate. We have focused our attention on the comparative aspect of GHRL, thus studying its expression in an amphibian seasonal breeder, Pelophylax esculentus, to verify the presence and localization, of Ghrl transcript variations during the frog reproductive cycle, in order to demonstrate that Pelophylax esculentus may represent a useful animal model to assess the role of GHRL in male fertility.
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Affiliation(s)
- Gaia Izzo
- Dipartimento di Medicina Sperimentale - Sez. Fisiologia umana e Funzioni Biologiche Integrate F. Bottazzi- Seconda Università di Napoli, via Costantinopoli 16 - 80138 Napoli - Italy
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23
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Ghrelin in female and male reproduction. INTERNATIONAL JOURNAL OF PEPTIDES 2010; 2010. [PMID: 20700403 PMCID: PMC2911616 DOI: 10.1155/2010/158102] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 12/23/2009] [Accepted: 01/09/2010] [Indexed: 11/23/2022]
Abstract
Ghrelin and one of its functional receptors, GHS-R1a (Growth Hormone Secretagogue Receptor 1a), were firstly studied about 15 years. Ghrelin is a multifunctional peptide hormone that affects several biological functions including food intake, glucose release, cell proliferation… Ghrelin and GHS-R1a are expressed in key cells of both male and female reproductive organs in several species including fishes, birds, and mammals suggesting a well-conserved signal through the evolution and a role in the control of fertility. Ghrelin could be a component of the complex series of nutrient sensors such as adipokines, and nuclear receptors, which regulate reproduction in function of the energy stores. The objective of this paper was to report the available information about the ghrelin system and its role at the level of the hypothalamic-pituitary-gonadal axis in both sexes.
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Sirotkin A, Rafay J, Kotwica J. Leptin controls rabbit ovarian function in vivo and in vitro: Possible interrelationships with ghrelin. Theriogenology 2009; 72:765-72. [DOI: 10.1016/j.theriogenology.2009.05.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 05/19/2009] [Accepted: 05/23/2009] [Indexed: 10/20/2022]
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25
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Forbes S, Li XF, Kinsey-Jones J, O’Byrne K. Effects of ghrelin on Kisspeptin mRNA expression in the hypothalamic medial preoptic area and pulsatile luteinising hormone secretion in the female rat. Neurosci Lett 2009; 460:143-7. [DOI: 10.1016/j.neulet.2009.05.060] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Accepted: 05/18/2009] [Indexed: 11/26/2022]
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Rago V, Aquila S, Guido C, Carpino A. Leptin and Its Receptor Are Expressed in the Testis and in the Epididymis of Young and Adult Pigs. Anat Rec (Hoboken) 2009; 292:736-45. [DOI: 10.1002/ar.20880] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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27
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Morphometrical and intracellular changes in rat ovaries following chronic administration of ghrelin. Tissue Cell 2009; 41:311-7. [PMID: 19264336 DOI: 10.1016/j.tice.2009.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 01/12/2009] [Accepted: 01/17/2009] [Indexed: 01/03/2023]
Abstract
The aim of our investigation was to examine the influence of chronic administration of ghrelin on the rat ovarian state. Morphometrical and intracellular changes in the ovary of 35-d female Wistar rats after sc injection of 1 nmol of ghrelin for 10 consecutive days were studied. Control animals (n=10) were injected with normal saline using similar method. The ovaries were collected on days 1 and 6 after last injection from each group and subjected to light microscopic morphometric and electron microscopic analysis. It was demonstrated that the number of corpora lutea was significantly lower and the number of ovarian follicles was higher in the treated group on days 1 and 6, than in control (P<0.01). Moreover, the mean diameter of each follicle, corpora lutea, luteal cell, theca layer, oocyte and zona plucida, but not of granulosa layer, as well as the whole ovarian volume were significantly lower in the treated animals at days 1 and 6 (P<0.05). Electron microscopic analysis also indicated some intracellular changes associated with apoptosis and cell death such as presence of secondary lysosome, apoptotic bodies, nuclear chromatin condensation as well as margination, nuclear segmentation and vacuolization of cytoplasm of granulosa and theca cells. Our observations provides novel evidences for inhibitory influence of ghrelin on rat ovarian structures and, therefore, for the role of ghrelin as suppressor of female reproductive system.
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28
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Tena-Sempere M. Ghrelin as a pleotrophic modulator of gonadal function and reproduction. ACTA ACUST UNITED AC 2008; 4:666-74. [DOI: 10.1038/ncpendmet1003] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Accepted: 09/29/2008] [Indexed: 11/09/2022]
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