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Carrillo B, Fernandez-Garcia JM, García-Úbeda R, Grassi D, Primo U, Blanco N, Ballesta A, Arevalo MA, Collado P, Pinos H. Neonatal inhibition of androgen activity alters the programming of body weight and orexinergic peptides differentially in male and female rats. Brain Res Bull 2024; 208:110898. [PMID: 38360152 DOI: 10.1016/j.brainresbull.2024.110898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/02/2024] [Accepted: 02/07/2024] [Indexed: 02/17/2024]
Abstract
The involvement of androgens in the regulation of energy metabolism has been demonstrated. The main objective of the present research was to study the involvement of androgens in both the programming of energy metabolism and the regulatory peptides associated with feeding. For this purpose, androgen receptors and the main metabolic pathways of testosterone were inhibited during the first five days of postnatal life in male and female Wistar rats. Pups received a daily s.c. injection from the day of birth, postnatal day (P) 1, to P5 of Flutamide (a competitive inhibitor of androgen receptors), Letrozole (an aromatase inhibitor), Finasteride (a 5-alpha-reductase inhibitor) or vehicle. Body weight, food intake and fat pads were measured. Moreover, hypothalamic Agouti-related peptide (AgRP), neuropeptide Y (NPY), orexin, and proopiomelanocortin (POMC) were analyzed by quantitative real-time polymerase chain reaction assay. The inhibition of androgenic activity during the first five days of life produced a significant decrease in body weight in females at P90 but did not affect this parameter in males. Moreover, the inhibition of aromatase decreased hypothalamic AgRP mRNA levels in males while the inhibition of 5α-reductase decreased hypothalamic AgRP and orexin mRNA levels in female rats. Finally, food intake and visceral fat, but not subcutaneous fat, were affected in both males and females depending on which testosterone metabolic pathway was inhibited. Our results highlight the differential involvement of androgens in the programming of energy metabolism as well as the AgRP and orexin systems during development in male and female rats.
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Affiliation(s)
- Beatriz Carrillo
- Department of Psychobiology, National University of Distance Education, Madrid, Spain; University Institute of Research-UNED-Institute of Health Carlos III (IMIENS), Madrid, Spain
| | - Jose Manuel Fernandez-Garcia
- University Institute of Research-UNED-Institute of Health Carlos III (IMIENS), Madrid, Spain; Faculty of Psychology, Universidad Villanueva Madrid, Madrid, Spain
| | - Rocío García-Úbeda
- Department of Psychobiology, National University of Distance Education, Madrid, Spain
| | - Daniela Grassi
- Department of Anatomy, Histology and Neuroscience, Autonomous University of Madrid, Madrid, Spain
| | - Ulises Primo
- Department of Psychobiology, National University of Distance Education, Madrid, Spain
| | - Noemí Blanco
- Department of Psychobiology, National University of Distance Education, Madrid, Spain; University Institute of Research-UNED-Institute of Health Carlos III (IMIENS), Madrid, Spain
| | - Antonio Ballesta
- Department of Psychobiology, Centro de Enseñanza Superior Cardenal Cisneros, Spain
| | - Maria Angeles Arevalo
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Madrid, Spain; Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Paloma Collado
- Department of Psychobiology, National University of Distance Education, Madrid, Spain; University Institute of Research-UNED-Institute of Health Carlos III (IMIENS), Madrid, Spain
| | - Helena Pinos
- Department of Psychobiology, National University of Distance Education, Madrid, Spain; University Institute of Research-UNED-Institute of Health Carlos III (IMIENS), Madrid, Spain.
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2
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Bodo C. A role for the androgen receptor in the sexual differentiation of the olfactory system in mice. BRAIN RESEARCH REVIEWS 2008; 57:321-31. [PMID: 17915335 PMCID: PMC2348186 DOI: 10.1016/j.brainresrev.2007.08.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 07/10/2007] [Accepted: 08/11/2007] [Indexed: 10/22/2022]
Abstract
Olfactory signals play a central role in the identification of a mating partner in rodents, and the behavioral response to these cues varies markedly between the sexes. As several other sexually dimorphic traits, this response is thought to differentiate as a result of exposure of the developing individual to gonadal steroids, but both the identity of the specific steroid signal and the neural structures targeted for differentiation on this particular case are largely unknown. The present review summarizes results obtained in our lab using genetic males affected by the testicular feminization syndrome (Tfm) as experimental model, and that led to the identification of a role for non-aromatized gonadal steroids acting through the androgen receptor (AR) in the differentiation of olfactory cues processing in mice. The existing literature about AR-mediated sexual differentiation of the CNS in animal models is discussed, along with potential targets for the action of non-aromatized gonadal steroids in either one of the subsystems that detect and process olfactory information in rodents.
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Affiliation(s)
- Cristian Bodo
- Graduate Program in Neuroscience, 1300 Jefferson Park Avenue, Room 1229, Jordan Hall, University of Virginia, Charlottesville, VA 22908, USA.
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3
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Segovia S, Garcia-Falgueras A, Carrillo B, Collado P, Pinos H, Perez-Laso C, Vinader-Caerols C, Beyer C, Guillamon A. Sexual dimorphism in the vomeronasal system of the rabbit. Brain Res 2006; 1102:52-62. [PMID: 16806123 DOI: 10.1016/j.brainres.2006.05.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2006] [Revised: 04/26/2006] [Accepted: 05/01/2006] [Indexed: 11/30/2022]
Abstract
Studies have shown that the vomeronasal system (VNS), an olfactory neural network that participates in the control of reproductive physiology and behavior, is sexually dimorphic in the rat. These works have also shown two main characteristics of brain sexual dimorphism: (a) dimorphism appears in neural networks related to reproduction and (b) it can present two morphological patterns: one in which males present greater morphological measures than females (male > female) and another in which the opposite is true (female > male). The present work extends the hypothesis to the rabbit, as a representative species of Lagomorpha. In addition, the locus coeruleus (LC), which is known to send rich noradrenergic projections to VNS structures, was also studied. Sex differences were found in: (a) the number of mitral, and dark and light granule cells (female > male) of the accessory olfactory bulb (AOB); (b) the medial amygdala (Me) and its dorsal (Med) and ventral (Mev) subdivisions, males showing greater values than females in volume and number of neurons, while in the posteromedial cortical amygdala (PMCo or C(3)), females show greater density of neurons than males and (c) the posteromedial division of the bed nucleus of the stria terminalis (BSTMP) in which males have more neurons than females. No sex differences were seen in the bed nucleus of the accessory olfactory tract (BAOT) and the LC. These results evidence that, as it was observed in rodents, sex differences are also seen in the VNS of Lagomorpha and that these sex differences present the two morphological patterns seen in Rodentia. Differences between orders are discussed with respect to the species-specific physiological and behavioral peculiarities.
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Affiliation(s)
- Santiago Segovia
- Departamento de Psicobiología, UNED, c/ Juan del Rosal, Madrid, Spain
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4
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Garcia-Falgueras A, Pinos H, Collado P, Pasaro E, Fernandez R, Jordan CL, Segovia S, Guillamon A. The role of the androgen receptor in CNS masculinization. Brain Res 2005; 1035:13-23. [PMID: 15713272 DOI: 10.1016/j.brainres.2004.11.060] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2004] [Indexed: 10/25/2022]
Abstract
The medial posterior region of the bed nucleus of the stria terminalis (BSTMP) and the locus coeruleus (LC) show opposite patterns of sexual dimorphism. The BSTMP in males is greater in volume and number of neurons than in females (male > female) while in the LC, the opposite is true (female > male). To investigate the possible role of the androgen receptor (AR) in the masculinization of these two structures, males with the testicular feminization mutation (Tfm) were compared to their control littermate males. No differences were seen in the number of neurons of the BSTMP between Tfm and their control littermate males, while in the LC, Tfm males have a greater number of neurons than their control littermate males. These results show that the AR is involved in the control of neuron number in the LC but not in the BSTMP. Results based on the LC suggest that when females have a larger brain area than males, masculinization in males may be achieved through the AR, with androgens perhaps decreasing cell survival.
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Collado P, Guillamón A, Pinos H, Pérez-Izquierdo MA, García-Falgueras A, Carrillo B, Rodríguez C, Panzica G. NADPH-diaphorase activity increases during estrous phase in the bed nucleus of the accessory olfactory tract in the female rat. Brain Res 2003; 983:223-9. [PMID: 12914984 DOI: 10.1016/s0006-8993(03)02973-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We investigated the presence of nitric oxide in the bed nucleus of the accessory olfactory tract (BAOT) in males, diestrous females and estrous females using NADPH-diaphorase. Our results demonstrate a significant increase in the density of the medium-stained cells in the estrous female rats suggesting that during estrous a specific subpopulation of nitrinergic cells are activated in the BAOT. This might be related to the physiological and behavioral changes that occurs in estrous.
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Affiliation(s)
- Paloma Collado
- Departamento de Psicobiologi;a, Universidad Nacional de Educación a Distancia, Ciudad Universitaria s/n, P.O. Box 60.148. 28040-, Madrid, Spain.
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6
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Vinader-Caerols C, Collado P, Segovia S, Guillamón A. Estradiol masculinizes the posteromedial cortical nucleus of the amygdala in the rat. Brain Res Bull 2000; 53:269-73. [PMID: 11113580 DOI: 10.1016/s0361-9230(00)00332-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It has been demonstrated that the posteromedial cortical amygdaloid nucleus (PMCo), is sexually dimorphic. It is shown (Experiment 1) that male orchidectomy on the day of birth (D1) decreases the volume and number of neurons of the PMCo, while a single injection of propionate testosterone to the female on D1 masculinizes the PMCo in this gender. Since male gonadectomy on D1 (Experiment 2) is counteracted by a single injection of estradiol benzoate in males it has been suggested that the masculinization of the PMCo is due to the aromatization of testosterone to estradiol in this structure. These findings support the hypothesis that the development of sex differences in structures that belong to the vomeronasal system are due to the aromatization of testosterone to estradiol shortly after birth.
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Affiliation(s)
- C Vinader-Caerols
- Area de Psicobiología, Facultad de Psicología, Universitat de València, Valencia, Spain
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7
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Segovia S, Guillamón A, del Cerro MC, Ortega E, Pérez-Laso C, Rodriguez-Zafra M, Beyer C. The development of brain sex differences: a multisignaling process. Behav Brain Res 1999; 105:69-80. [PMID: 10553691 DOI: 10.1016/s0166-4328(99)00083-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
In order to account for the development of sex differences in the brain, we took, as an integrative model, the vomeronasal pathway, which is involved in the control of reproductive physiology and behavior. The fact that brain sex differences take place in complex neural networks will help to develop a motivational theory of sex differences in reproductive behaviors. We also address the classic genomic actions in which three agents (the hormone, the intracellular receptor, and the transcription function) play an important role in brain differentiation, but we also point out refinements that such a theory requires if we want to account of the existence of two morphological patterns of sex differences in the brain, one in which males show greater morphological measures (neuron numbers and/or volume) than females and the opposite. Moreover, we also consider very important processes closely related to neuronal afferent input and membrane excitability for the developing of sex differences. Neurotransmission associated to metabotropic and ionotropic receptors, neurotrophic factors, neuroactive steroids that alter membrane excitability, cross-talk (and/or by-pass) phenomena, and second messenger pathways appear to be involved in the development of brain sex differences. The sexual differentiation of the brain and reproductive behavior is regarded as a cellular multisignaling process.
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Affiliation(s)
- S Segovia
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain.
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8
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Collado P, Segovia S, Guillamón A. Development of sex differences in the bed nucleus of the accessory olfactory tract in the rat. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 1998; 109:99-108. [PMID: 9706395 DOI: 10.1016/s0165-3806(98)00068-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
In the present study, we investigate the development of sex differences in the bed nucleus of the accessory olfactory tract (BAOT), a sexually dimorphic structure in which masculinization of male rats depends on the level of postnatal estradiol. Male and female Wistar rats were sacrificed postnatally when they were 1, 3, 7, 15, 45 and 60 days old, and stereological methods were used to estimate the volume and number of neurons in the BAOT of the subjects. With respect to volume, sex differences were established from P15. In relation to the number of neurons, the males acquire their adult morphological parameter by P15, while females show a decrease (P3), increase (from P3 to P15) and later decrease (from P15 to P45). Sex differences from P3 to P7 might be related to greater cell death in the BAOT of the females. These results support the hypothesis that both male and female rats reach their adult morphological pattern within this sexually dimorphic nucleus in an active manner.
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Affiliation(s)
- P Collado
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
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9
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Abstract
In the early eighties we found sex differences in the vomeronasal organ (VNO) and hypothesized that the vomeronasal system (VNS), a complex neural network involved in the control of reproductive behavior, might be sexually dimorphic. At that time sex differences had already been described for some structures that receive VNO input, such as the medial amygdala, the medial preoptic area, the ventromedial hypothalamic nucleus, and the ventral region of the premammillary nucleus. Since then, we have shown sex differences in the accessory olfactory bulb (AOB), the bed nucleus of the accessory olfactory tract (BAOT), and the bed nucleus of the stria terminalis (BST). When new VNS connections were found, all of them ended in nuclei that present sex differences. In general, sex differences in the olfactory system show two morphological patterns: one in which males present greater morphological measures than females, and just the opposite. To explain the morphometric measures of males in the latter, it has been hypothesized that androgens serve as inhibitors. Our work on the involvement of the GABA(A) receptor in the development of AOB and maternal behavior sex differences also suggests that neonatal changes in neuronal membrane permeability to the ion Cl- differences. This might be the first animal model to help us to understand the situation in which human genetic and gonadal sex do not agree with brain and behavioral sex. Finally, we stress that sex differences in the VNS constitute a neurofunctional model for understanding sex differences in reproductive behaviors.
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Affiliation(s)
- A Guillamón
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Ciudad Universitaria, Madrid, Spain
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10
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Abstract
The role of androgens in vertebrate females has been overlooked until recently. We examine the functional significance of androgens in females by reviewing studies that document relatively high levels of circulating plasma androgens, androgen receptors, or androgen-metabolizing enzymes in females. Among the mechanisms of androgenic action identified are enhanced neuron survival, stimulation of muscle satellite cell proliferation, alteration of ion current kinetics, and release of somatostatin. These mechanisms are not sex specific and thus we hypothesize that androgens play a significant role in normal female development. We encourage study in this nontraditional research area.
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Affiliation(s)
- N L Staub
- Biology Department, Gonzaga University, Spokane, Washington, 99258, USA.
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11
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Pérez-Laso C, Segovia S, Collado P, Rodríguez-Zafra M, Del Abril A, Guillamón A. Estradiol masculinizes the number of accessory olfactory bulb mitral cells in the rat. Brain Res Bull 1997; 42:227-30. [PMID: 8995334 DOI: 10.1016/s0361-9230(96)00260-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Orchidectomized males injected with a single dose of estradiol benzoate on the day of birth (D1) showed mitral cell numbers in the accessory olfactory bulb similar to those of control males. However, orchidectomized males that received no additional estradiol benzoate treatment and those orchidectomized and given a single dose of dihydrotestosterone on D1 showed decreases in the number of accessory olfactory bulb mitral cells compared with control males. These results support the notion that the presence of estradiol immediately after birth induces the masculinization of mitral cells number in the accessory olfactory bulb.
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Affiliation(s)
- C Pérez-Laso
- Departamento de Psicobiología, Universidad Nacional de Educación a Distancia, Madrid, Spain
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12
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Affiliation(s)
- M D Madeira
- Department of Anatomy, Porto Medical School, Portugal
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