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Matsuda KI, Takahashi T, Morishita S, Tanaka M. Histological analysis of neuronal changes in the olfactory cortex during pregnancy. Heliyon 2024; 10:e26780. [PMID: 38444488 PMCID: PMC10912243 DOI: 10.1016/j.heliyon.2024.e26780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 03/07/2024] Open
Abstract
Fluctuations in olfactory sensitivity are widely known to occur during pregnancy and may be responsible for hyperemesis gravidarum. These changes are thought to be caused by structural and functional alterations in neurons in response to marked changes of the hormonal milieu. In this study, we examined changes in neurons in the olfactory cortex during pregnancy and after delivery in rats. Dendritic spine densities were measured in the piriform cortex (PIR) and posterolateral cortical amygdala (COApl), which are involved in olfaction. The results showed increased numbers of dendritic spines in the PIR in mid-pregnancy and in the COApl during early and late pregnancy, but not in the motor area of the cerebral cortex, indicating a correlation with changes in olfactory sensitivity during pregnancy. Immunohistochemical analysis of expression of ovarian hormone receptors in these brain regions revealed a decrease in the number of estrogen receptor α-positive cells during pregnancy in the PIR and during pregnancy and the postpartum period in the COApl. Regarding pregnancy-related peptide hormones, oxytocin receptors were expressed in the PIR and COApl, while prolactin receptors were not found in these regions. Accordingly, oxytocin-containing neurites were distributed in both regions. These results suggest that the balance of these hormonal signals has an effect on olfactory sensitivity in pregnant females.
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Affiliation(s)
- Ken Ichi Matsuda
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Tomoki Takahashi
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Sae Morishita
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Masaki Tanaka
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
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2
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Kunimura Y, Iwata K, Ishii H, Ozawa H. Chronic estradiol exposure suppresses luteinizing hormone surge without affecting kisspeptin neurons and estrogen receptor alpha in anteroventral periventricular nucleus†. Biol Reprod 2024; 110:90-101. [PMID: 37774351 DOI: 10.1093/biolre/ioad129] [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: 03/27/2023] [Revised: 09/20/2023] [Accepted: 09/22/2023] [Indexed: 10/01/2023] Open
Abstract
Mammalian ovulation is induced by a luteinizing hormone surge, which is triggered by elevated plasma estrogen levels; however, chronic exposure to high levels of estradiol is known to inhibit luteinizing hormone secretion. In the present study, we hypothesized that the inhibition of the luteinizing hormone surge by chronic estradiol exposure is due to the downregulation of the estrogen receptor alpha in kisspeptin neurons at hypothalamic anteroventral periventricular nucleus, which is known as the gonadotropin-releasing hormone/luteinizing hormone surge generator. Animals exposed to estradiol for 2 days showed an luteinizing hormone surge, whereas those exposed for 14 days showed a significant suppression of luteinizing hormone. Chronic estradiol exposure did not affect the number of kisspeptin neurons and the percentage of kisspeptin neurons with estrogen receptor alpha or c-Fos in anteroventral periventricular nucleus, but it did affect the number of kisspeptin neurons in arcuate nucleus. Furthermore, chronic estradiol exposure did not affect gonadotropin-releasing hormone neurons. In the pituitary, 14-day estradiol exposure significantly reduced the expression of Lhb mRNA and LHβ-immunoreactive areas. Gonadotropin-releasing hormone-induced luteinizing hormone release was also reduced significantly by 14-day estradiol exposure. We revealed that the suppression of an luteinizing hormone surge by chronic estradiol exposure was induced in association with the significant reduction in kisspeptin neurons in arcuate nucleus, luteinizing hormone expression in the pituitary, and pituitary responsiveness to gonadotropin-releasing hormone, and this was not caused by changes in the estrogen receptor alpha-expressing kisspeptin neurons in anteroventral periventricular nucleus and gonadotropin-releasing hormone neurons, which are responsible for estradiol positive feedback.
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Affiliation(s)
- Yuyu Kunimura
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Kinuyo Iwata
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Hirotaka Ishii
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Hitoshi Ozawa
- Department of Anatomy and Neurobiology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
- Department of Physical Therapy, Faculty of Health Science, Bukkyo University, Kyoto, Japan
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3
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Torres Irizarry VC, Jiang Y, He Y, Xu P. Hypothalamic Estrogen Signaling and Adipose Tissue Metabolism in Energy Homeostasis. Front Endocrinol (Lausanne) 2022; 13:898139. [PMID: 35757435 PMCID: PMC9218066 DOI: 10.3389/fendo.2022.898139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 04/29/2022] [Indexed: 11/30/2022] Open
Abstract
Obesity has become a global epidemic, and it is a major risk factor for other metabolic disorders such as type 2 diabetes and cardiometabolic disease. Accumulating evidence indicates that there is sex-specific metabolic protection and disease susceptibility. For instance, in both clinical and experimental studies, males are more likely to develop obesity, insulin resistance, and diabetes. In line with this, males tend to have more visceral white adipose tissue (WAT) and less brown adipose tissue (BAT) thermogenic activity, both leading to an increased incidence of metabolic disorders. This female-specific fat distribution is partially mediated by sex hormone estrogens. Specifically, hypothalamic estrogen signaling plays a vital role in regulating WAT distribution, WAT beiging, and BAT thermogenesis. These regulatory effects on adipose tissue metabolism are primarily mediated by the activation of estrogen receptor alpha (ERα) in neurons, which interacts with hormones and adipokines such as leptin, ghrelin, and insulin. This review discusses the contribution of adipose tissue dysfunction to obesity and the role of hypothalamic estrogen signaling in preventing metabolic diseases with a particular focus on the VMH, the central regulator of energy expenditure and glucose homeostasis.
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Affiliation(s)
- Valeria C. Torres Irizarry
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, The University of Illinois at Chicago, Chicago, IL, United States
- Department of Physiology and Biophysics, The University of Illinois at Chicago, Chicago, IL, United States
| | - Yuwei Jiang
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, The University of Illinois at Chicago, Chicago, IL, United States
- Department of Physiology and Biophysics, The University of Illinois at Chicago, Chicago, IL, United States
- *Correspondence: Yuwei Jiang, ; Yanlin He, ; Pingwen Xu,
| | - Yanlin He
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA, United States
- *Correspondence: Yuwei Jiang, ; Yanlin He, ; Pingwen Xu,
| | - Pingwen Xu
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, The University of Illinois at Chicago, Chicago, IL, United States
- Department of Physiology and Biophysics, The University of Illinois at Chicago, Chicago, IL, United States
- *Correspondence: Yuwei Jiang, ; Yanlin He, ; Pingwen Xu,
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4
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Huang KP, Ronveaux CC, de Lartigue G, Geary N, Asarian L, Raybould HE. Deletion of leptin receptors in vagal afferent neurons disrupts estrogen signaling, body weight, food intake and hormonal controls of feeding in female mice. Am J Physiol Endocrinol Metab 2019; 316:E568-E577. [PMID: 30753113 PMCID: PMC6482667 DOI: 10.1152/ajpendo.00296.2018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Deletion of the leptin receptor from vagal afferent neurons (VAN) using a conditional deletion (Nav1.8/LepRfl/fl) results in an obese phenotype with increased food intake and lack of exogenous cholecystokinin (CCK)-induced satiation in male mice. Female mice are partially protected from weight gain and increased food intake in response to ingestion of high-fat (HF) diets. However, whether the lack of leptin signaling in VAN leads to an obese phenotype or disruption of hypothalamic-pituitary-gonadal axis function in female mice is unclear. Here, we tested the hypothesis that leptin signaling in VAN is essential to maintain estrogen signaling and control of food intake, energy expenditure, and adiposity in female mice. Female Nav1.8/LepRfl/fl mice gained more weight, had increased gonadal fat mass, increased meal number in the dark phase, and increased total food intake compared with wild-type controls. Resting energy expenditure was unaffected. The decrease in food intake produced by intraperitoneal injection of CCK (3 μg/kg body wt) was attenuated in female Nav1.8/LepRfl/fl mice compared with wild-type controls. Intraperitoneal injection of ghrelin (100 μg/kg body wt) increased food intake in Nav1.8/LepRfl/fl mice but not in wild-type controls. Ovarian steroidogenesis was suppressed, resulting in decreased plasma estradiol, which was accompanied by decreased expression of estrogen receptor-1 (Esr1) in VAN but not in the hypothalamic arcuate nucleus. These data suggest that the absence of leptin signaling in VAN is accompanied by disruption of estrogen signaling in female mice, leading to an obese phenotype possibly via altered control of feeding behavior.
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Affiliation(s)
- Kuei-Pin Huang
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California Davis , Davis, California
| | - Charlotte C Ronveaux
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California Davis , Davis, California
| | - Guillaume de Lartigue
- John B. Pierce Laboratory/Cellular and Molecular Physiology Department, Yale University School of Medicine , New Haven, Connecticut
| | - Nori Geary
- Department of Psychiatry, Weill Medical College of Cornell University , New York, New York
| | - Lori Asarian
- Department of Medicine-Immunobiology, Robert Larner College of Medicine, University of Vermont , Burlington, Vermont
| | - Helen E Raybould
- Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California Davis , Davis, California
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Yamaguchi S, Abe Y, Maejima S, Tsukahara S. Sexual experience reduces neuronal activity in the central part of the medial preoptic nucleus in male rats during sexual behavior. Neurosci Lett 2018; 685:155-159. [DOI: 10.1016/j.neulet.2018.08.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 07/30/2018] [Accepted: 08/27/2018] [Indexed: 10/28/2022]
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Matsuda KI, Hashimoto T, Kawata M. Intranuclear Mobility of Estrogen Receptor: Implication for Transcriptional Regulation. Acta Histochem Cytochem 2018; 51:129-136. [PMID: 30279614 PMCID: PMC6160615 DOI: 10.1267/ahc.18023] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 07/31/2018] [Indexed: 11/22/2022] Open
Abstract
The estrogen receptor (ER) is a ligand-dependent transcription factor that has two subtypes: ERα and ERβ. ERs regulate transcription of estrogen-responsive genes through interactions with multiple intranuclear components, such as cofactors and the nuclear matrix. Live cell imaging using fluorescent protein-labeled ERs has revealed that ligand-activated ERs are highly mobile in the nucleus, with transient association with the DNA and nuclear matrix. Scaffold attachment factor B (SAFB) 1 and its paralogue, SAFB2, are nuclear matrix-binding proteins that negatively modulate ERα-mediated transcription. Expression of SAFB1 and SAFB2 reduces the mobility of ERα in the presence of ligand. This regulatory machinery is emerging as an epigenetic-like mechanism that alters transcriptional activity through control of intranuclear molecular mobility.
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Affiliation(s)
- Ken Ichi Matsuda
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine
| | - Takashi Hashimoto
- Division of Anatomy and Neuroscience, Department of Morphological and Physiological Sciences, University of Fukui Faculty of Medical Sciences
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Santi D, Spaggiari G, Gilioli L, Potì F, Simoni M, Casarini L. Molecular basis of androgen action on human sexual desire. Mol Cell Endocrinol 2018; 467:31-41. [PMID: 28893567 DOI: 10.1016/j.mce.2017.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022]
Abstract
Reproduction is a fundamental process for the species maintenance and the propagation of genetic information. The energy expenditure for mating is overtaken by motivational stimuli, such as orgasm, finely regulated by steroid hormones, gonadotropins, neurotransmitters and molecules acting in the brain and peripheral organs. These functions are often investigated using animal models and translated to humans, where the androgens action is mediated by nuclear and membrane receptors converging in the regulation of both long-term genomic and rapid non-genomic signals. In both sexes, testosterone is a central player of this game and is involved in the regulation of sexual desire and arousal, and, finally, in reproduction through cognitive and peripheral physiological mechanisms which may decline with aging and circadian disruption. Finally, genetic variations impact on reproductive behaviours, resulting in sex-specific effect and different reproductive strategies. In this review, androgen actions on sexual desire are evaluated, focusing on the molecular levels of interaction.
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Affiliation(s)
- Daniele Santi
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Unit of Endocrinology, Department of Medicine, Endocrinology, Metabolism and Geriatrics, Azienda OU of Modena, Modena, Italy
| | - Giorgia Spaggiari
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Unit of Endocrinology, Department of Medicine, Endocrinology, Metabolism and Geriatrics, Azienda OU of Modena, Modena, Italy
| | - Lisa Gilioli
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Center for Genomic Research, University of Modena and Reggio Emilia, Modena, Italy
| | - Francesco Potì
- Department of Neurosciences, University of Parma, Parma, Italy
| | - Manuela Simoni
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Unit of Endocrinology, Department of Medicine, Endocrinology, Metabolism and Geriatrics, Azienda OU of Modena, Modena, Italy; Center for Genomic Research, University of Modena and Reggio Emilia, Modena, Italy.
| | - Livio Casarini
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy; Center for Genomic Research, University of Modena and Reggio Emilia, Modena, Italy
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8
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Balabanov IE, Matsuda KI, Mori H, Yamada S, Kitagawa K, Yamamoto Y, Tsukahara S, Tanaka M. Neuronal activity in the sagittalis nucleus of the hypothalamus after ovarian steroid hormone manipulation and sexual behavior in female rat. Neurosci Lett 2018; 671:25-28. [PMID: 29421537 DOI: 10.1016/j.neulet.2018.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 01/24/2018] [Accepted: 02/05/2018] [Indexed: 11/26/2022]
Abstract
During extended observation of estrogen receptor (ER) α-immunoreactive neurons in the hypothalamus, we previously identified a novel nucleus, the Sagittalis Nucleus of the Hypothalamus (SGN), in the interstitial area between the arcuate nucleus and the ventromedial hypothalamic nucleus. The SGN exhibits sexual dimorphism in its volume and cell count, and estrous cycle related variations in ERα-immunoreactivity. These characteristics of the SGN implicate the nucleus in sex-biased brain functions and behaviors. In this study, we examined involvement of the SGN in sexual arousal in female rats. Immunohistochemical staining of c-Fos, a marker of neuronal activity was performed after administration of an estrus-inducing dose of estrogen and progesterone in ovariectomized female rats. Analysis of microscopic images showed a significant increase in the number of c-Fos-expressing neurons in the SGN following hormonal manipulation. Moreover, neuronal activity in the region exhibited a further increase after each animal was coupled with a male and allowed to mate. These results suggest that the SGN plays an important role in sexual activity in female rat.
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Affiliation(s)
- Ivaylo Evgueniev Balabanov
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; Graduate School of Mental Health and Neuroscience (MHeNS), Maastricht University, Maastricht, The Netherlands; European Graduate School of Neuroscience (Euron)-Japan Double Degree Program, The Netherlands
| | - Ken Ichi Matsuda
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan.
| | - Hiroko Mori
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Shunji Yamada
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Keito Kitagawa
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Yukina Yamamoto
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan; Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan; Kyoto College of Nutritional & Medical Sciences, Kyoto, Japan
| | - Shinji Tsukahara
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama, Japan
| | - Masaki Tanaka
- Department of Anatomy and Neurobiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
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9
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Influence of preoptic estradiol on behavioral and neural response to cocaine in female Sprague-Dawley rats. Psychopharmacology (Berl) 2018; 235:663-672. [PMID: 29204804 PMCID: PMC5823731 DOI: 10.1007/s00213-017-4800-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 11/01/2017] [Indexed: 02/08/2023]
Abstract
RATIONALE Systemic estradiol (E2) increases the behavioral and neural response to cocaine. Where in the brain E2 acts to modulate cocaine response is not entirely clear. Evidence supports a role in this modulation for several candidate regions, including the medial preoptic area (mPOA). OBJECTIVES This study examined whether manipulation of E2 in the mPOA modulates differing behavioral responses to cocaine and whether this is reflected in differing levels of c-Fos in the NAc following cocaine administration. METHODS Female rats received ovariectomies and bilateral cannulations of the mPOA. They then received either artificial cerebrospinal fluid (aCSF) or E2 microinjections into the mPOA the day before receiving systemic injections of saline or cocaine (5 or 10 mg/kg). Conditioned-place preference (CPP) to cocaine and locomotor activation were then obtained. RESULTS Animals receiving 10 mg/kg, but not 5 mg/kg, cocaine developed significant CPP, and those receiving E2 into the mPOA expressed greater CPP than those receiving microinjections of only aCSF at both doses (p < 0.05, d > 0.80). Cocaine also caused significant psychomotor activation, but this was not dependent on microinjection of E2 in the mPOA. Finally, animals that received cocaine had increased NAc core and shell c-Fos relative to animals that received saline, with animals receiving both E2 microinjections and systemic cocaine expressing the highest activation in the caudal NAc, compared to rats receiving aCSF microinjections and systemic cocaine (p = 0.05, d = 0.70). CONCLUSIONS These results indicate that E2 in the mPOA facilitates the behavioral response and neural activation that follows cocaine administration. Furthermore, they confirm the close relationship between the mPOA and cocaine response.
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10
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Matsuda KI, Uchiyama K, Mori H, Maejima S, Yamaguchi S, Tanaka M, Tsukahara S. Sexual behavior-associated c-Fos induction in the sagittalis nucleus of the hypothalamus in male rat. Neurosci Lett 2017; 661:104-107. [DOI: 10.1016/j.neulet.2017.09.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/13/2017] [Accepted: 09/26/2017] [Indexed: 10/18/2022]
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Ribeiro AB, Leite CM, Kalil B, Franci CR, Anselmo-Franci JA, Szawka RE. Kisspeptin regulates tuberoinfundibular dopaminergic neurones and prolactin secretion in an oestradiol-dependent manner in male and female rats. J Neuroendocrinol 2015; 27:88-99. [PMID: 25453900 DOI: 10.1111/jne.12242] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 10/20/2014] [Accepted: 11/26/2014] [Indexed: 12/11/2022]
Abstract
Prolactin (PRL) secretion is inhibited by hypothalamic dopamine. Kisspeptin controls luteinising hormone (LH) secretion and is also involved in PRL regulation. We further investigated the effect of kisspeptin-10 (Kp-10) on the activity of tuberoinfundibular dopaminergic (TIDA) neurones and the role of oestradiol (E2 ) in this mechanism. Female and male rats were injected with i.c.v. Kp-10 and evaluated for PRL release and the activity of dopamine terminals in the median eminence (ME) and neurointermediate lobe of the pituitary (NIL). Kp-10 at the doses of 0.6 and 3 nmol increased plasma PRL and decreased 4-dihydroxyphenylacetic acid (DOPAC) levels in the ME and NIL of ovariectomised (OVX), E2 -treated rats but had no effect in OVX. In gonad-intact males, 3 nmol Kp-10 increased PRL secretion and decreased DOPAC levels in the ME but not in the NIL. Castrated males treated with either testosterone or E2 also displayed increased PRL secretion and reduced ME DOPAC in response to Kp-10, whereas castrated rats receiving oil or dihydrotestosterone were unresponsive. By contrast, the LH response to Kp-10 was not E2 -dependent in either females or males. Additionally, immunohistochemical double-labelling demonstrated that TIDA neurones of male rats contain oestrogen receptor (ER)-α, with a higher proportion of neurones expressing ERα than in dioestrous females. The dopaminergic neurones of periventricular hypothalamic nucleus displayed much lower ERα expression. Thus, TIDA neurones express ERα in male and female rats, and kisspeptin increases PRL secretion through inhibition of TIDA neurones in an E2 -dependent manner in both sexes. These findings provide new evidence about the role of kisspeptin in the regulation of dopamine and PRL.
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Affiliation(s)
- A B Ribeiro
- Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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12
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Mori H, Matsuda KI, Yamawaki M, Kawata M. Estrogenic regulation of histamine receptor subtype H1 expression in the ventromedial nucleus of the hypothalamus in female rats. PLoS One 2014; 9:e96232. [PMID: 24805361 PMCID: PMC4013143 DOI: 10.1371/journal.pone.0096232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 04/04/2014] [Indexed: 02/03/2023] Open
Abstract
Female sexual behavior is controlled by central estrogenic action in the ventromedial nucleus of the hypothalamus (VMN). This region plays a pivotal role in facilitating sex-related behavior in response to estrogen stimulation via neural activation by several neurotransmitters, including histamine, which participates in this mechanism through its strong neural potentiating action. However, the mechanism through which estrogen signaling is linked to the histamine system in the VMN is unclear. This study was undertaken to investigate the relationship between estrogen and histamine receptor subtype H1 (H1R), which is a potent subtype among histamine receptors in the brain. We show localization of H1R exclusively in the ventrolateral subregion of the female VMN (vl VMN), and not in the dorsomedial subregion. In the vl VMN, abundantly expressed H1R were mostly colocalized with estrogen receptor α. Intriguingly, H1R mRNA levels in the vl VMN were significantly elevated in ovariectomized female rats treated with estrogen benzoate. These data suggest that estrogen can amplify histamine signaling by enhancing H1R expression in the vl VMN. This enhancement of histamine signaling might be functionally important for allowing neural excitation in response to estrogen stimulation of the neural circuit and may serve as an accelerator of female sexual arousal.
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Affiliation(s)
- Hiroko Mori
- Department of Medical Education, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto, Japan
- * E-mail:
| | - Ken-Ichi Matsuda
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto, Japan
| | - Masanaga Yamawaki
- Department of Medical Education, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto, Japan
| | - Mitsuhiro Kawata
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto, Japan
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13
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Matsuda KI, Yanagisawa M, Sano K, Ochiai I, Musatov S, Okoshi K, Tsukahara S, Ogawa S, Kawata M. Visualisation and characterisation of oestrogen receptor α-positive neurons expressing green fluorescent protein under the control of the oestrogen receptor α promoter. Eur J Neurosci 2013; 38:2242-9. [PMID: 23601009 DOI: 10.1111/ejn.12227] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Accepted: 03/21/2013] [Indexed: 12/20/2022]
Abstract
Oestrogen receptor (ER)α plays important roles in the development and function of various neuronal systems through activation by its ligands, oestrogens. To visualise ERα-positive neurons, we generated transgenic (tg) mice expressing green fluorescent protein (GFP) under the control of the ERα promoter. In three independent tg lines, GFP-positive neurons were observed in areas previously reported to express ERα mRNA, including the lateral septum, bed nucleus of the stria terminalis, medial preoptic nucleus (MPO), hypothalamus, and amygdala. In these areas, GFP signals mostly overlapped with ERα immunoreactivity. GFP fluorescence was seen in neurites and cell bodies of neurons. In addition, the network and detailed structure of neurites were visible in dissociated and slice cultures of hypothalamic neurons. We examined the effect of oestrogen deprivation by ovariectomy on the structure of the GFP-positive neurons. The area of ERα-positive cell bodies in the bed nucleus of the stria terminalis and MPO was measured by capturing the GFP signal and was found to be significantly smaller in ovariectomy mice than in control mice. When neurons in the MPO were infected with an adeno-associated virus that expressed small hairpin RNA targeting the ERα gene, an apparent induction of GFP was observed in this area, suggesting a negative feedback mechanism in which ERα controls expression of the ERα gene itself. Thus, the ERα promoter-GFP tg mice will be useful to analyse the development and plastic changes of the structure of ERα-expressing neurons and oestrogen and its receptor-mediated neuronal responses.
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Affiliation(s)
- Ken Ichi Matsuda
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine Graduate School of Medical Science, 465 Kawaramachi Hirokoji, Kamigyoku, Kyoto 602-8566, Japan.
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14
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Mori H, Matsuda KI, Tsukahara S, Kawata M. Intrauterine position affects estrogen receptor α expression in the ventromedial nucleus of the hypothalamus via promoter DNA methylation. Endocrinology 2010; 151:5775-81. [PMID: 20926584 DOI: 10.1210/en.2010-0646] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
There is well-established evidence in many mammalian species for effects of the intrauterine position (IUP) (the sex-specific positioning of the embryo) on postnatal brain function and behavior. We found that the IUP affects estrogen receptor (ER)α expression in adult female rats in the ventrolateral region of the hypothalamic ventromedial nucleus (vlVMH), which is associated with sexual behavior. The ERα expression level in the vlVMH was higher in females that developed in utero between two male siblings (2M females) than in those that developed between female siblings (2F females). We also found that the cytosine methylation status across the ERα promoter in the vlVMH was affected by the IUP, with greater methylation in 2F females. These findings showed a negative correlation between ERα expression levels in the vlVMH and methylation frequency in the ERα promoter. This suggests that genomic methylation sustains the effect of the fetal IUP on ERα expression in the vlVMH.
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Affiliation(s)
- Hiroko Mori
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
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Functional requirement of AgRP and NPY neurons in ovarian cycle-dependent regulation of food intake. Proc Natl Acad Sci U S A 2009; 106:15932-7. [PMID: 19805233 DOI: 10.1073/pnas.0904747106] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In female mammals including rodents and humans, feeding decreases during the periovulatory period of the ovarian cycle, which coincides with a surge in circulating estrogen levels. Ovariectomy increases food intake, which can be normalized by estrogen treatment at a dose and frequency mimicking those during the estrous cycle. Furthermore, administration of estrogen to rodents potently inhibits food intake. Despite these well-known effects of estrogen, neuronal subtypes that mediate estrogen's anorexigenic effects have not been identified. In this study, we show that changes in hypothalamic expression of agouti-related protein (Agrp) and neuropeptide Y (Npy) coincide with the cyclic changes in feeding across the estrous cycle. These cyclic changes in feeding are abolished in mice with degenerated AgRP neurons even though these mice cycle normally. Central administration of 17beta-estradiol (E2) decreases food intake in controls but not in mice lacking the AgRP neurons. Furthermore, E2 treatment suppresses fasting-induced c-Fos activation in AgRP and NPY neurons and blunts the refeeding response. Surprisingly, although estrogen receptor alpha (ERalpha) is the key mediator of estrogen's anorexigenic effects, we find that expression of ERalpha is completely excluded from AgRP and NPY neurons in the mouse hypothalamus, suggesting that estrogen may regulate these neurons indirectly via presynaptic neurons that express ERalpha. This study indicates that neurons coexpressing AgRP and NPY are functionally required for the cyclic changes in feeding across estrous cycle and that AgRP and NPY neurons are essential mediators of estrogen's anorexigenic function.
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Abstract
The sagittalis nucleus (SGN) of the hypothalamus is a newly-identified nucleus that is located in the interstitial area between the arcuate and ventromedial nuclei of the rat hypothalamus and for which the long axis of the nucleus is oriented sagittally. Interestingly, the SGN exhibits structural and physiological sex differences, as defined by Nissl staining and oestrogen receptor (ER)alpha immunoreactivity (-ir), being larger in males than females. The structural sex difference is established by sex steroid action in neonates because the treatment of female pups with testosterone propionate masculinised the SGN. The phenotypical sex difference in ERalpha-ir is mediated hormonally in adulthood. Ovariectomy of female rats caused a significant increase in ERalpha-ir in the SGN, and eliminated the physiological sex difference, but with recovery to the level of gonad-intact females when given oestradiol replacement. Adult females have oestrous cycle-related variations in ERalpha-ir in the SGN, with levels at a nadir during the evening of pro-oestrous. The discovery of the SGN, a target of sex steroid action, provides a new opportunity for explaining hormonal regulation of sexually-differentiated behavioural and endocrine functions.
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Affiliation(s)
- H Mori
- Department of Anatomy and Neurobiology, Kyoto Prefectural University of Medicine, Kyoto, Japan
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