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Buckley M, Jacob WP, Bortey L, McClain M, Ritter AL, Godfrey A, Munneke AS, Ramachandran S, Kenis S, Kolnik JC, Olofsson S, Adkins R, Kutoloski T, Rademacher L, Heinecke O, Alva A, Beets I, Francis MM, Kowalski JR. Cell non-autonomous signaling through the conserved C. elegans glycopeptide hormone receptor FSHR-1 regulates cholinergic neurotransmission. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.10.578699. [PMID: 38405708 PMCID: PMC10888917 DOI: 10.1101/2024.02.10.578699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Modulation of neurotransmission is key for organismal responses to varying physiological contexts such as during infection, injury, or other stresses, as well as in learning and memory and for sensory adaptation. Roles for cell autonomous neuromodulatory mechanisms in these processes have been well described. The importance of cell non-autonomous pathways for inter-tissue signaling, such as gut-to-brain or glia-to-neuron, has emerged more recently, but the cellular mechanisms mediating such regulation remain comparatively unexplored. Glycoproteins and their G protein-coupled receptors (GPCRs) are well-established orchestrators of multi-tissue signaling events that govern diverse physiological processes through both cell-autonomous and cell non-autonomous regulation. Here, we show that follicle stimulating hormone receptor, FSHR-1, the sole Caenorhabditis elegans ortholog of mammalian glycoprotein hormone GPCRs, is important for cell non-autonomous modulation of synaptic transmission. Inhibition of fshr-1 expression reduces muscle contraction and leads to synaptic vesicle accumulation in cholinergic motor neurons. The neuromuscular and locomotor defects in fshr-1 loss-of-function mutants are associated with an underlying accumulation of synaptic vesicles, build-up of the synaptic vesicle priming factor UNC-10/RIM, and decreased synaptic vesicle release from cholinergic motor neurons. Restoration of FSHR-1 to the intestine is sufficient to restore neuromuscular activity and synaptic vesicle localization to fshr-1- deficient animals. Intestine-specific knockdown of FSHR-1 reduces neuromuscular function, indicating FSHR-1 is both necessary and sufficient in the intestine for its neuromuscular effects. Re-expression of FSHR-1 in other sites of endogenous expression, including glial cells and neurons, also restored some neuromuscular deficits, indicating potential cross-tissue regulation from these tissues as well. Genetic interaction studies provide evidence that downstream effectors gsa-1 / Gα S , acy-1 /adenylyl cyclase and sphk-1/ sphingosine kinase and glycoprotein hormone subunit orthologs, GPLA-1/GPA2 and GPLB-1/GPB5, are important for FSHR-1 modulation of the NMJ. Together, our results demonstrate that FSHR-1 modulation directs inter-tissue signaling systems, which promote synaptic vesicle release at neuromuscular synapses.
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Sogorb MA, Candela H, Estévez J, Vilanova E. Investigation of the Effects of Metallic Nanoparticles on Fertility Outcomes and Endocrine Modification of the Hypothalamic-Pituitary-Gonadal Axis. Int J Mol Sci 2023; 24:11687. [PMID: 37511445 PMCID: PMC10380468 DOI: 10.3390/ijms241411687] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/11/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Nanotechnology is a very disruptive twenty-first-century revolution that will allow social and economic welfare to increase although it also involves a significant human exposure to nanoparticles. The aim of the present study was to contribute to the elucidation on whether metallic nanoparticles have a potential to induce fertility impairments. Regulatory studies that observed official OECD guidelines 415, 416 and 422 have failed to detect any fertility alterations caused by nanoparticle exposure. However, the scientific literature provides evidence that some nanoparticles may cause gonad impairments although the actual impact on fertility remains uncertain. This aim of the present study is to revisit the previously published RNAseq studies by analyzing the effects of several nanoparticles on the transcriptome of T98G human glioblastoma cells given that glial cells are known to play a pivotal role in the regulation of gonadotropin releasing hormone neurons. We found evidence that nanoparticles impair the gonadotropin releasing hormone receptor pathway and several related biological process like, among others, the cellular response to follicular stimulating hormone, cellular response to gonadotropin stimulus, cellular response to hormone stimulus, response to steroid hormone, ovulation cycle and response to estradiol. We propose that nanoparticles interfere with the ability of glial cells to regulate gonadotropin-releasing hormone neurons and, subsequently, the hypothalamic-pituitary-gonadal axis, potentially leading to fertility impairments. To our knowledge, this is the first proposal of a mode of action based on endocrine disruption for explaining the possible effects of nanoparticles on fertility. Whether these finding can be extended to other types of nanoparticles requires further investigation.
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Affiliation(s)
- Miguel A Sogorb
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Héctor Candela
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Jorge Estévez
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Avenida de la Universidad s/n, 03202 Elche, Spain
| | - Eugenio Vilanova
- Instituto de Bioingeniería, Universidad Miguel Hernández de Elche, Avenida de la Universidad s/n, 03202 Elche, Spain
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Kour A, Deb SM, Nayee N, Niranjan SK, Raina VS, Mukherjee A, Gupta ID, Patil CS. Novel insights into genome-wide associations in Bos indicus reveal genetic linkages between fertility and growth. Anim Biotechnol 2023; 34:39-55. [PMID: 34120566 DOI: 10.1080/10495398.2021.1932520] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Bos indicus breed Sahiwal, famous for its optimum performance, has so far been genetically improved for performance traits based on phenotypic records and the genomic knowhow regarding genes, regions and biological processes underlying the complex quantitative traits is lacking. In this context, a Genome-wide Association Study was performed for fertility and growth traits in Sahiwal cattle to shed light on its genomic profile. A total of 46 SNPs were found associated with the traits at genome-wide suggestive threshold of P ≤ 10-4. USP32, LRPPRC, PLA2G10, RRN3 and ASAP1 were identified as putative candidate genes for body weight at different ages. However, several genes mapped for growth traits like GREB1, PLA2G10, RAD51C, BIRC6, TEX14 and PEBP4 had significant physiological underpinnings in determining fertility of the animals. Moreover, Quantitative trait loci (QTL) identification revealed potential overlaps with the already reported QTLs for both fertility and growth for most of the traits. Further, candidate SNP enrichment analysis revealed an enriched biological process for birth weight with a significant reproductive role. Based on the findings, genetic linkages underlying fertility and growth could be discerned in Sahiwal population and may be utilized for improving fertility traits in future.
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Affiliation(s)
- Aneet Kour
- ICAR-National Dairy Research Institute, Karnal, Haryana, India
| | | | - Nilesh Nayee
- National Dairy Development Board, Anand, Gujarat, India
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Ni W, Zhang J, Wang B, Liang F, Bao L, Li P, Fang Y. Actin related protein 2/3 complex subunit 1 up-regulation in the hypothalamus prevents high-fat diet induced obesity. Eur J Neurosci 2023; 57:64-77. [PMID: 36382618 DOI: 10.1111/ejn.15871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 10/10/2022] [Accepted: 11/10/2022] [Indexed: 11/17/2022]
Abstract
Obesity is a major health crisis in the modern society. Studies have shown that the consumption of a high-fat diet (HFD) induces hypothalamic inflammation and leptin resistance, which consequently favours body mass gain. Actin related protein 2/3 complex subunit 1 (ARPC1B), an actin-binding protein, is highly expressed in immune cells. Recent studies have shown that ARPC1B has a certain anti-inflammatory effect. While ARPC1B expression is decreased in the hypothalamus of mice fed a HFD, the role of ARPC1B in HFD-induced obesity remains unclear. Thus, we investigated whether ARPC1B up-regulation in the hypothalamic arcuate nucleus (ARC) could inhibit the development of obesity. Herein, ARPC1B overexpression lentiviral particles were stereotaxically injected into the ARC of male C57BL/6J mice (7 weeks old) fed with HFD. Overexpression of ARPC1B in the hypothalamic ARC attenuated HFD-induced ARC inflammation, reduced body-weight gain and feed efficiency. Furthermore, up-regulation of ARC ARPC1B improved the glucose tolerance and reduced subcutaneous/epididymal fat mass accumulation, which decreased the serum total cholesterol, serum triglyceride and leptin levels. In addition, upon ARPC1B overexpression in the hypothalamic ARC, intraperitoneal injection of leptin increased the phosphorylation level of signal transducer and activator of transcription 3 (STAT3), an important transcription factor for leptin's action, in the ARC of obese mice. Accordingly, we suggest that up-regulation of ARPC1B in the hypothalamic ARC may improve the HFD-induced hypothalamic inflammation and leptin resistance. Our findings demonstrate that ARPC1B is a promising target for the treatment of diet-induced obesity.
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Affiliation(s)
- Weimin Ni
- Department of Neurosurgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
| | - Jie Zhang
- Department of Neurosurgery, Sanbo Brain Hospital Capital Medical University, Beijing, P.R. China
| | - Bing Wang
- Department of Neurosurgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
| | - Feng Liang
- Department of Neurosurgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
| | - Long Bao
- Department of Neurosurgery, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
| | - Pengfei Li
- Graduate School of Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
| | - Yan Fang
- Teaching and Research Section of Anatomy, College of Basic Medical Sciences, Jinzhou Medical University, Jinzhou, Liaoning, P.R. China
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Merchán M, Coveñas R, Plaza I, Abecia JA, Palacios C. Anatomy of hypothalamic and diencephalic nuclei involved in seasonal fertility regulation in ewes. Front Vet Sci 2023; 10:1101024. [PMID: 36876003 PMCID: PMC9978410 DOI: 10.3389/fvets.2023.1101024] [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: 11/17/2022] [Accepted: 01/31/2023] [Indexed: 02/18/2023] Open
Abstract
In this study, we describe in detail the anatomy of nuclei involved in seasonal fertility regulation (SFR) in ewes. For this purpose, the intergeniculate leaflet of the visual thalamus, the caudal hypothalamic arcuate nucleus, and suprachiasmatic, paraventricular and supraoptic nuclei of the rostral hypothalamus were morphometrically and qualitatively analyzed in Nissl-stained serial sections, in the three anatomical planes. In addition, data were collected on calcium-binding proteins and cell phenotypes after immunostaining alternate serial sections for calretinin, parvalbumin and calbindin. For a complete neuroanatomical study, glial architecture was assessed by immunostaining and analyzing alternate sections for glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA1). The results showed a strong microglial and astroglia reaction around the hypothalamic nuclei of interest and around the whole 3rd ventricle of the ewe brain. Moreover, we correlated cytoarchitectonic coordinates of panoramic serial sections with their macroscopic localization and extension in midline sagittal-sectioned whole brain to provide guidelines for microdissecting nuclei involved in SFR.
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Affiliation(s)
- Miguel Merchán
- Animal Production Area, Department of Construction and Agronomy, Faculty of Agricultural and Environmental Sciences, University of Salamanca, Salamanca, Spain.,Laboratory of Neuroanatomy of the Peptidergic Systems, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain.,Recognized Research Group - Molecular Bases of Development (Grupo de Investigación Reconocido - Bases Moleculares del Desarrollo - GIR-BMD), University of Salamanca, Salamanca, Spain
| | - Rafael Coveñas
- Laboratory of Neuroanatomy of the Peptidergic Systems, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain.,Recognized Research Group - Molecular Bases of Development (Grupo de Investigación Reconocido - Bases Moleculares del Desarrollo - GIR-BMD), University of Salamanca, Salamanca, Spain
| | - Ignacio Plaza
- Auditory Neuroplasticity Laboratory, Institute for Neuroscience of Castilla y León (INCYL), University of Salamanca, Salamanca, Spain
| | - José Alfonso Abecia
- Environmental Science Institute (IUCA), University of Zaragoza, Zaragoza, Spain
| | - Carlos Palacios
- Animal Production Area, Department of Construction and Agronomy, Faculty of Agricultural and Environmental Sciences, University of Salamanca, Salamanca, Spain
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A Transcriptomic Analysis of T98G Human Glioblastoma Cells after Exposure to Cadmium-Selenium Quantum Dots Mainly Reveals Alterations in Neuroinflammation Processes and Hypothalamus Regulation. Int J Mol Sci 2022; 23:ijms23042267. [PMID: 35216387 PMCID: PMC8877384 DOI: 10.3390/ijms23042267] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 02/13/2022] [Accepted: 02/16/2022] [Indexed: 01/04/2023] Open
Abstract
Quantum dots are nanoparticles with very promising biomedical applications. However, before these applications can be authorized, a complete toxicological assessment of quantum dots toxicity is needed. This work studied the effects of cadmium-selenium quantum dots on the transcriptome of T98G human glioblastoma cells. It was found that 72-h exposure to 40 µg/mL (a dose that reduces cell viability by less than 10%) alters the transcriptome of these cells in biological processes and molecular pathways, which address mainly neuroinflammation and hormonal control of hypothalamus via the gonadotropin-releasing hormone receptor. The biological significance of neuroinflammation alterations is still to be determined because, unlike studies performed with other nanomaterials, the expression of the genes encoding pro-inflammatory interleukins is down-regulated rather than up-regulated. The hormonal control alterations of the hypothalamus pose a new concern about a potential adverse effect of quantum dots on fertility. In any case, more studies are needed to clarify the biological relevance of these findings, and especially to assess the real risk of toxicity derived from quantum dots exposure appearing in physiologically relevant scenarios.
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Vanacker C, Defazio RA, Sykes CM, Moenter SM. A role for glial fibrillary acidic protein (GFAP)-expressing cells in the regulation of gonadotropin-releasing hormone (GnRH) but not arcuate kisspeptin neuron output in male mice. eLife 2021; 10:68205. [PMID: 34292152 PMCID: PMC8337074 DOI: 10.7554/elife.68205] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/21/2021] [Indexed: 01/05/2023] Open
Abstract
GnRH neurons are the final central neural output regulating fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (KNDy neurons) are considered the main regulator of GnRH output. GnRH and KNDy neurons are surrounded by astrocytes, which can modulate neuronal activity and communicate over distances. Prostaglandin E2 (PGE2), synthesized primarily by astrocytes, increases GnRH neuron activity and downstream pituitary release of luteinizing hormone (LH). We hypothesized that glial fibrillary acidic protein (GFAP)-expressing astrocytes play a role in regulating GnRH and/or KNDy neuron activity and LH release. We used adeno-associated viruses to target designer receptors exclusively activated by designer drugs (DREADDs) to GFAP-expressing cells to activate Gq- or Gi-mediated signaling. Activating Gq signaling in the preoptic area, near GnRH neurons, but not in the arcuate, increases LH release in vivo and GnRH firing in vitro via a mechanism in part dependent upon PGE2. These data suggest that astrocytes can activate GnRH/LH release in a manner independent of KNDy neurons.
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Affiliation(s)
- Charlotte Vanacker
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - R Anthony Defazio
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - Charlene M Sykes
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - Suzanne M Moenter
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States.,Internal Medicine, University of Michigan, Ann Arbor, United States.,Obstetrics & Gynecology, University of Michigan, Ann Arbor, United States.,Reproductive Sciences Program, University of Michigan, Ann Arbor, United States
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Gao W, Wang Z, Wang H, Li H, Huang C, Shen Y, Ma X, Sun H. Neurons and Astrocytes in Ventrolateral Periaqueductal Gray Contribute to Restraint Water Immersion Stress-Induced Gastric Mucosal Damage via the ERK1/2 Signaling Pathway. Int J Neuropsychopharmacol 2021; 24:666-676. [PMID: 34000028 PMCID: PMC8378083 DOI: 10.1093/ijnp/pyab028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 03/15/2021] [Accepted: 05/12/2021] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND The restraint water immersion stress (RWIS) model includes both psychological and physical stimulation, which may lead to gastrointestinal disorders and cause gastric mucosal damage. The ventrolateral periaqueductal gray (VLPAG) contributes to gastrointestinal function, but whether it is involved in RWIS-induced gastric mucosal damage has not yet been reported. METHODS The expression of glial fibrillary acidic protein, neuronal c-Fos, and phosphorylated extracellular signal regulated kinase 1/2 in the VLPAG after RWIS was assessed using western blotting and immunocytochemical staining methods. Lateral ventricle injection of astrocytic toxin L-a-aminoadipate and treatment with extracellular signal-regulated kinase (ERK)1/2 signaling pathway inhibitor PD98059 were further used to study protein expression and distribution in the VLPAG after RWIS. RESULTS The expression of c-Fos, glial fibrillary acidic protein, and phosphorylated extracellular signal regulated kinase 1/2 in the VLPAG significantly increased following RWIS and peaked at 1 hour after RWIS. Lateral ventricle injection of the astrocytic toxin L-a-aminoadipate significantly alleviated gastric mucosal injury and decreased the activation of neurons and astrocytes. Treatment with the ERK1/2 signaling pathway inhibitor PD98059 obviously suppressed gastric mucosal damage as well as the RWIS-induced activation of neurons and astrocytes in the VLPAG. CONCLUSIONS These results suggested that activation of VLPAG neurons and astrocytes induced by RWIS through the ERK1/2 signaling pathway may play a critical role in RWIS-induced gastric mucosa damage.
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Affiliation(s)
- Wenting Gao
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Zepeng Wang
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Hui Wang
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Huimin Li
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Chenxu Huang
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Yangyang Shen
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China
| | - Xiaoli Ma
- Research Center of Basic Medicine, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China,Correspondence: Xiaoli Ma, PhD, Jinan Central Hospital, Cheeloo College of Medicine, Shandong University ()
| | - Haiji Sun
- Key Laboratory of Animal Resistance Biology of Shandong Province, College of Life Science, Shandong Normal University, Jinan, China,Haiji Sun, PhD, College of Life Science, Shandong Normal University ()
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Proteomic study of hypothalamus in pigs exposed to heat stress. BMC Vet Res 2020; 16:286. [PMID: 32787853 PMCID: PMC7424663 DOI: 10.1186/s12917-020-02505-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 07/30/2020] [Indexed: 11/17/2022] Open
Abstract
Background With evidence of warming climates, it is important to understand the effects of heat stress in farm animals in order to minimize production losses. Studying the changes in the brain proteome induced by heat stress may aid in understanding how heat stress affects brain function. The hypothalamus is a critical region in the brain that controls the pituitary gland, which is responsible for the secretion of several important hormones. In this study, we examined the hypothalamic protein profile of 10 pigs (15 ± 1 kg body weight), with five subjected to heat stress (35 ± 1 °C; relative humidity = 90%) and five acting as controls (28 ± 3 °C; RH = 90%). Result The isobaric tags for relative and absolute quantification (iTRAQ) analysis of the hypothalamus identified 1710 peptides corresponding to 360 proteins, including 295 differentially expressed proteins (DEPs), 148 of which were up-regulated and 147 down-regulated, in heat-stressed animals. The Ingenuity Pathway Analysis (IPA) software predicted 30 canonical pathways, four functional groups, and four regulatory networks of interest. The DEPs were mainly concentrated in the cytoskeleton of the pig hypothalamus during heat stress. Conclusions In this study, heat stress significantly increased the body temperature and reduced daily gain of body weight in pigs. Furthermore, we identified 295 differentially expressed proteins, 147 of which were down-regulated and 148 up-regulated in hypothalamus of heat stressed pigs. The IPA showed that the DEPs identified in the study are involved in cell death and survival, cellular assembly and organization, and cellular function and maintenance, in relation to neurological disease, metabolic disease, immunological disease, inflammatory disease, and inflammatory response. We hypothesize that a malfunction of the hypothalamus may destroy the host physical and immune function, resulting in decreased growth performance and immunosuppression in heat stressed pigs.
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Braga DV, Wanderley Picanço-Diniz DL, Herculano Matos Oliveira KR, Luz WL, Soares de Moraes SA, Fonseca Passos AC, de Jesus Oliveira Batista E, Grisólia A, Herculano AM. Adenosine A1 receptors modulate the Na+-Hypertonicity induced glutamate release in hypothalamic glial cells. Neurochem Int 2019; 126:64-68. [DOI: 10.1016/j.neuint.2019.02.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 02/11/2019] [Accepted: 02/18/2019] [Indexed: 02/09/2023]
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Ayala C, Pennacchio GE, Soaje M, Bittencourt JC, Celis ME, Jahn GA, Valdez SR, Seltzer AM. Differential effects of hypo- and hyperthyroidism on remodeling of contacts between neurons expressing the neuropeptide EI and tyrosine hydroxylase in hypothalamic areas of the male rat. Peptides 2019; 113:1-10. [PMID: 30590076 DOI: 10.1016/j.peptides.2018.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/10/2018] [Accepted: 12/22/2018] [Indexed: 12/11/2022]
Abstract
The Neuropeptide EI (NEI, glutamic acid- isoleucine amide) participates in neuroendocrine function. Previously we demonstrated that NEI concentration is regulated by thyroid hormones in discrete hypothalamic areas in rats. We observed that the thyroid status affects the dopaminergic regulation of the pituitary hormones. In this study we explored possible interactions between NEI and tyrosine hydroxylase (TH) containing elements in selected hypothalamic areas of male rats. Neuronal somas, terminals and boutons were assessed by confocal microscopy, in hypo- and hyperthyroid animals. We observed a remodeling of the contacts between the TH and NEI immunoreactive elements in the incerto-hypothalamic area (IHy, also known as rostromedial zona incerta) according to thyroid function. However, in the dorsolateral zone of the peduncular part of the lateral hypothalamus (DL-PLH) the thyroid hormones affect the dendritic trees of the neurons without perturbing the overall NEI/TH contacts. Also, we demonstrated that TRH Receptor 1 (TRH-R1) is colocalized in NEI immunoreactive neurons in the peduncular part of the lateral hypothalamus (PLH) and NEI precursor mRNA expression increased by hypothyroidism indicating that NEI neurons are responsive to the feedback mechanisms of the Hypothalamic Pituitary-Thyroid Axis (HPT). In conclusion, the hypothyroid status seems to increase the interactions between the NEI neurons and the dopaminergic pathways while hyperthyroidism either decreases or displays no effects. Altogether these observations support the participation of the IHy and PLH NEI as a modulating component of the HPT suggesting that altered neuroendocrine, behavioral and cognitive dysfunctions induced by dysthyroidism could be in part mediated by NEI.
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Affiliation(s)
- Carolina Ayala
- Laboratorio de Neurobiología, Instituto de Embriología e Histología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina; Laboratorio de Ciencias Fisiológicas, Cátedra de Bacteriología y Virología Médicas, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
| | - Gisela E Pennacchio
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, UNCuyo, 5500, Mendoza, Argentina
| | - Marta Soaje
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Instituto de Fisiología, Facultad de Ciencias Médicas, UNCuyo, 5500, Mendoza, Argentina
| | - Jackson C Bittencourt
- Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, Brazil
| | - María E Celis
- Laboratorio de Ciencias Fisiológicas, Cátedra de Bacteriología y Virología Médicas, Facultad de Ciencias Médicas, Universidad Nacional de Córdoba, 5000, Córdoba, Argentina
| | - Graciela A Jahn
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina
| | - Susana R Valdez
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo (IMBECU-CONICET), Centro Científico Tecnológico (CCT), 5500, Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, UNCuyo, 5500, Mendoza, Argentina.
| | - Alicia M Seltzer
- Laboratorio de Neurobiología, Instituto de Embriología e Histología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo (UNCuyo), 5500, Mendoza, Argentina
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Milesi S, Simonneaux V, Klosen P. Downregulation of Deiodinase 3 is the earliest event in photoperiodic and photorefractory activation of the gonadotropic axis in seasonal hamsters. Sci Rep 2017; 7:17739. [PMID: 29255151 PMCID: PMC5735130 DOI: 10.1038/s41598-017-17920-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/04/2017] [Indexed: 02/06/2023] Open
Abstract
In seasonal rodents, reproduction is activated by a long photoperiod. Furthermore, maintaining an inhibitory short photoperiod for over 20 weeks triggers a spontaneous reactivation of the gonadotropic axis called photorefractoriness. Photoactivation is proposed to involve melatonin, hypothalamic thyroid hormones (TH) and (Arg) (Phe)-amide peptides. The mechanisms involved in photorefractoriness are so far unknown. We analyzed the dynamic changes in long photoperiod- and photorefractory-induced activation of reproduction in both Syrian and Djungarian hamsters to validate the current model of photoactivation and to uncover the mechanisms involved in photorefractoriness. We detected a conserved early inhibition of expression of the TH catabolizing enzyme deiodinase 3 (Dio3) in tanycytes, associated with a late decrease of the TH transporter MCT8. This suggests that an early peak of hypothalamic TH may be involved in both photoinduced and photorefractory reactivation. In photoactivation, Dio3 downregulation is followed by an upregulation of Dio2, which is not observed in photorefraction. The upregulation of (Arg) (Phe)-amides occurs several weeks after the initial Dio3 inhibition. In conclusion, we uncovered a so far unreported early inhibition of Dio3. This early downregulation of Dio3 is reinforced by an upregulation of Dio2 in photoactivated hamsters. In photorefractoriness, the Dio3 downregulation might be sufficient to reactivate the gonadotropic axis.
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Affiliation(s)
- Sébastien Milesi
- Institute of Cellular and Integrative Neuroscience, CNRS, University of Strasbourg, 67084, Strasbourg, Cedex, France
| | - Valérie Simonneaux
- Institute of Cellular and Integrative Neuroscience, CNRS, University of Strasbourg, 67084, Strasbourg, Cedex, France.
| | - Paul Klosen
- Institute of Cellular and Integrative Neuroscience, CNRS, University of Strasbourg, 67084, Strasbourg, Cedex, France.
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Kumar S, Singh U, Goswami C, Singru PS. Transient receptor potential vanilloid 5 (TRPV5), a highly Ca 2+ -selective TRP channel in the rat brain: relevance to neuroendocrine regulation. J Neuroendocrinol 2017; 29. [PMID: 28235149 DOI: 10.1111/jne.12466] [Citation(s) in RCA: 14] [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: 04/06/2016] [Revised: 02/21/2017] [Accepted: 02/21/2017] [Indexed: 11/28/2022]
Abstract
Recent studies suggest an important role for transient receptor potential vanilloid (TRPV) ion channels in neural and neuroendocrine regulation. The TRPV subfamily consists of six members: TRPV1-6. While the neuroanatomical and functional correlates of TRPV1-4 have been studied extensively, relevant information about TRPV5 and TRPV6, which are highly selective for Ca2+ , is limited. We detected TRPV5 mRNA expression in the olfactory bulb, cortex, hypothalamus, hippocampus, midbrain, brainstem and cerebellum of the rat. TRPV5-immunoreactive neurones were conspicuously seen in the hypothalamic paraventricular (PVN), supraoptic (SON), accessory neurosecretory (ANS), supraoptic nucleus, retrochiasmatic part (SOR), arcuate (ARC) and medial tuberal nuclei, hippocampus, midbrain, brainstem and cerebellum. Glial cells also showed TRPV5-immunoreactivity. To test the neuroendocrine relevance of TRPV5, we focused on vasopressin, oxytocin and cocaine- and amphetamine-regulated transcript (CART) as representative candidate markers with which TRPV5 may co-exist. In the hypothalamic neurones, co-expression of TRPV5 was observed with vasopressin (PVN: 50.73±3.82%; SON: 75.91±2.34%; ANS: 49.12±4.28%; SOR: 100%) and oxytocin (PVN: 6.88±1.21; SON: 63.34±5.69%; ANS: 20.4±4.14; SOR: 86.5±1.74%). While ARC neurones express oestrogen receptors, 17β-oestradiol regulates TRPV5, as well as CART neurones and astrocytes, in the ARC. Furthermore, ARC CART neurones are known to project to the preoptic area, and innervate and regulate GnRH neurones. Using double-immunofluorescence, glial fibrillary acidic protein-labelled astrocytes and the majority of CART neurones in the ARC showed TRPV5-immunoreactivity. Following iontophoresis of retrograde neuronal tracer, cholera toxin β (CtB) into the anteroventral periventricular nucleus and median preoptic nucleus, retrograde accumulation of CtB was observed in most TRPV5-equipped ARC CART neurones. Next, we determined the response of TRPV5-elements in the ARC during the oestrous cycle. Compared to pro-oestrus, a significant increase (P<.001) in the percentage of TRPV5-expressing CART neurones was observed during oestrus, metoestrus, and dioestrus. TRPV5-immunoreactivity in the astrocytes, however, showed a significant increase during metoestrus and dioestrus. We suggest that the TRPV5 ion channel may serve as an important regulator of neural and neuroendocrine pathways in the brain.
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Affiliation(s)
- S Kumar
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, India
| | - U Singh
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, India
| | - C Goswami
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, India
| | - P S Singru
- School of Biological Sciences, National Institute of Science Education and Research (NISER), Bhubaneswar, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, India
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14
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Acaz-Fonseca E, Avila-Rodriguez M, Garcia-Segura LM, Barreto GE. Regulation of astroglia by gonadal steroid hormones under physiological and pathological conditions. Prog Neurobiol 2016; 144:5-26. [DOI: 10.1016/j.pneurobio.2016.06.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 06/05/2016] [Indexed: 01/07/2023]
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15
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Chowen JA, Argente-Arizón P, Freire-Regatillo A, Frago LM, Horvath TL, Argente J. The role of astrocytes in the hypothalamic response and adaptation to metabolic signals. Prog Neurobiol 2016; 144:68-87. [PMID: 27000556 DOI: 10.1016/j.pneurobio.2016.03.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 02/09/2016] [Accepted: 03/04/2016] [Indexed: 12/19/2022]
Abstract
The hypothalamus is crucial in the regulation of homeostatic functions in mammals, with the disruption of hypothalamic circuits contributing to chronic conditions such as obesity, diabetes mellitus, hypertension, and infertility. Metabolic signals and hormonal inputs drive functional and morphological changes in the hypothalamus in attempt to maintain metabolic homeostasis. However, the dramatic increase in the incidence of obesity and its secondary complications, such as type 2 diabetes, have evidenced the need to better understand how this system functions and how it can go awry. Growing evidence points to a critical role of astrocytes in orchestrating the hypothalamic response to metabolic cues by participating in processes of synaptic transmission, synaptic plasticity and nutrient sensing. These glial cells express receptors for important metabolic signals, such as the anorexigenic hormone leptin, and determine the type and quantity of nutrients reaching their neighboring neurons. Understanding the mechanisms by which astrocytes participate in hypothalamic adaptations to changes in dietary and metabolic signals is fundamental for understanding the neuroendocrine control of metabolism and key in the search for adequate treatments of metabolic diseases.
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Affiliation(s)
- Julie A Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, CIBER de Obesidad Fisiopatología de la Obesidad y Nutrición (CIBEROBN). Instituto de Salud Carlos III, Madrid, Spain.
| | - Pilar Argente-Arizón
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, CIBER de Obesidad Fisiopatología de la Obesidad y Nutrición (CIBEROBN). Instituto de Salud Carlos III, Madrid, Spain; Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
| | - Alejandra Freire-Regatillo
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, CIBER de Obesidad Fisiopatología de la Obesidad y Nutrición (CIBEROBN). Instituto de Salud Carlos III, Madrid, Spain; Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
| | - Laura M Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, CIBER de Obesidad Fisiopatología de la Obesidad y Nutrición (CIBEROBN). Instituto de Salud Carlos III, Madrid, Spain; Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
| | - Tamas L Horvath
- Program in Integrative Cell Signaling and Neurobiology of Metabolism, Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación la Princesa, CIBER de Obesidad Fisiopatología de la Obesidad y Nutrición (CIBEROBN). Instituto de Salud Carlos III, Madrid, Spain; Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain
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Bosler O, Girardet C, Franc JL, Becquet D, François-Bellan AM. Structural plasticity of the circadian timing system. An overview from flies to mammals. Front Neuroendocrinol 2015; 38:50-64. [PMID: 25703789 DOI: 10.1016/j.yfrne.2015.02.001] [Citation(s) in RCA: 18] [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: 07/01/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 12/22/2022]
Abstract
The circadian timing system orchestrates daily variations in physiology and behavior through coordination of multioscillatory cell networks that are highly plastic in responding to environmental changes. Over the last decade, it has become clear that this plasticity involves structural changes and that the changes may be observed not only in central brain regions where the master clock cells reside but also in clock-controlled structures. This review considers experimental data in invertebrate and vertebrate model systems, mainly flies and mammals, illustrating various forms of structural circadian plasticity from cellular to circuit-based levels. It highlights the importance of these plastic events in the functional adaptation of the clock to the changing environment.
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Affiliation(s)
- Olivier Bosler
- Aix-Marseille Université, CNRS, CRN2M, UMR 7286, Faculté de médecine, secteur nord, Boulevard Pierre Dramard, CS 80011, F-13344 Marseille cedex 15, France.
| | - Clémence Girardet
- Aix-Marseille Université, CNRS, CRN2M, UMR 7286, Faculté de médecine, secteur nord, Boulevard Pierre Dramard, CS 80011, F-13344 Marseille cedex 15, France.
| | - Jean-Louis Franc
- Aix-Marseille Université, CNRS, CRN2M, UMR 7286, Faculté de médecine, secteur nord, Boulevard Pierre Dramard, CS 80011, F-13344 Marseille cedex 15, France
| | - Denis Becquet
- Aix-Marseille Université, CNRS, CRN2M, UMR 7286, Faculté de médecine, secteur nord, Boulevard Pierre Dramard, CS 80011, F-13344 Marseille cedex 15, France
| | - Anne-Marie François-Bellan
- Aix-Marseille Université, CNRS, CRN2M, UMR 7286, Faculté de médecine, secteur nord, Boulevard Pierre Dramard, CS 80011, F-13344 Marseille cedex 15, France
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17
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Semaphorin7A regulates neuroglial plasticity in the adult hypothalamic median eminence. Nat Commun 2015; 6:6385. [PMID: 25721933 PMCID: PMC4351556 DOI: 10.1038/ncomms7385] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 01/26/2015] [Indexed: 11/08/2022] Open
Abstract
Reproductive competence in mammals depends on the projection of gonadotropin-releasing hormone (GnRH) neurons to the hypothalamic median eminence (ME) and the timely release of GnRH into the hypothalamic-pituitary-gonadal axis. In adult rodents, GnRH neurons and the specialized glial cells named tanycytes periodically undergo cytoskeletal plasticity. However, the mechanisms that regulate this plasticity are still largely unknown. We demonstrate that Semaphorin7A, expressed by tanycytes, plays a dual role, inducing the retraction of GnRH terminals and promoting their ensheathment by tanycytic end feet via the receptors PlexinC1 and Itgb1, respectively. Moreover, Semaphorin7A expression is regulated during the oestrous cycle by the fluctuating levels of gonadal steroids. Genetic invalidation of Semaphorin7A receptors in mice induces neuronal and glial rearrangements in the ME and abolishes normal oestrous cyclicity and fertility. These results show a role for Semaphorin7A signalling in mediating periodic neuroglial remodelling in the adult ME during the ovarian cycle.
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18
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Cloutier CT, Coxworth JE, Hawkes K. Age-related decline in ovarian follicle stocks differ between chimpanzees (Pan troglodytes) and humans. AGE (DORDRECHT, NETHERLANDS) 2015; 37:9746. [PMID: 25651885 PMCID: PMC4317403 DOI: 10.1007/s11357-015-9746-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 01/14/2015] [Indexed: 06/04/2023]
Abstract
Similarity in oldest parturitions in humans and great apes suggests that we maintain ancestral rates of ovarian aging. Consistent with that hypothesis, previous counts of primordial follicles in postmortem ovarian sections from chimpanzees (Pan troglodytes) showed follicle stock decline at the same rate that human stocks decline across the same ages. Here, we correct that finding with a chimpanzee sample more than three times larger than the previous one, which also allows comparison into older ages. Analyses show depletion rates similar until about age 35, but after 35, the human counts continue to fall with age, while the change is much less steep in chimpanzees. This difference implicates likely effects on ovarian dynamics from other physiological systems that are senescing at different rates, and, potentially, different perimenopausal experience for chimpanzees and humans.
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Affiliation(s)
- Christina T. Cloutier
- />Department of Anthropology, University of Utah, 270 S 1400 E, Room 102, Salt Lake City, UT 84112 USA
| | - James E. Coxworth
- />Department of Anthropology, University of Utah, 270 S 1400 E, Room 102, Salt Lake City, UT 84112 USA
- />Utah Population Database, University of Utah, Salt Lake City, UT USA
| | - Kristen Hawkes
- />Department of Anthropology, University of Utah, 270 S 1400 E, Room 102, Salt Lake City, UT 84112 USA
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19
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Giacobini P. Shaping the Reproductive System: Role of Semaphorins in Gonadotropin-Releasing Hormone Development and Function. Neuroendocrinology 2015; 102:200-15. [PMID: 25967979 DOI: 10.1159/000431021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 04/28/2015] [Indexed: 11/19/2022]
Abstract
The semaphorin proteins, which contribute to the morphogenesis and homeostasis of a wide range of systems, are among the best-studied families of guidance cues. Much recent research has focused on the role of semaphorins in the development and adult activity of hormone systems and, reciprocally, how circulating reproductive hormones regulate their expression and function. Specifically, several reports have focused on the molecular mechanisms underlying the effects of semaphorins on the migration, survival and structural and functional plasticity of neurons that secrete gonadotropin-releasing hormone (GnRH), essential for the acquisition and maintenance of reproductive competence in mammals. Alterations in the development of this neuroendocrine system lead to anomalous or absent GnRH secretion, resulting in heterogeneous reproductive disorders such as congenital hypogonadotropic hypogonadism (CHH) or other conditions characterized by infertility or subfertility. This review summarizes current knowledge of the role of semaphorins and their receptors on the development, differentiation and plasticity of the GnRH system. In addition, the involvement of genetic deficits in semaphorin signaling in some forms of CHH in humans is discussed.
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Affiliation(s)
- Paolo Giacobini
- Inserm, Laboratory of Development and Plasticity of the Neuroendocrine Brain, Jean-Pierre Aubert Research Centre, U1172, School of Medicine, University of Lille, and Institut de Médecine Prédictive et de Recherche Thérapeutique, IFR114, Lille, France
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20
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Hansberg-Pastor V, González-Arenas A, Piña-Medina AG, Camacho-Arroyo I. Sex Hormones Regulate Cytoskeletal Proteins Involved in Brain Plasticity. Front Psychiatry 2015; 6:165. [PMID: 26635640 PMCID: PMC4653291 DOI: 10.3389/fpsyt.2015.00165] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 11/02/2015] [Indexed: 01/22/2023] Open
Abstract
In the brain of female mammals, including humans, a number of physiological and behavioral changes occur as a result of sex hormone exposure. Estradiol and progesterone regulate several brain functions, including learning and memory. Sex hormones contribute to shape the central nervous system by modulating the formation and turnover of the interconnections between neurons as well as controlling the function of glial cells. The dynamics of neuron and glial cells morphology depends on the cytoskeleton and its associated proteins. Cytoskeletal proteins are necessary to form neuronal dendrites and dendritic spines, as well as to regulate the diverse functions in astrocytes. The expression pattern of proteins, such as actin, microtubule-associated protein 2, Tau, and glial fibrillary acidic protein, changes in a tissue-specific manner in the brain, particularly when variations in sex hormone levels occur during the estrous or menstrual cycles or pregnancy. Here, we review the changes in structure and organization of neurons and glial cells that require the participation of cytoskeletal proteins whose expression and activity are regulated by estradiol and progesterone.
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Affiliation(s)
- Valeria Hansberg-Pastor
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Aliesha González-Arenas
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Ana Gabriela Piña-Medina
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México , Mexico City , Mexico
| | - Ignacio Camacho-Arroyo
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México , Mexico City , Mexico
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21
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Vatta MS, Bianciotti LG, Guil MJ, Hope SI. Regulation of the Norepinephrine Transporter by Endothelins. HORMONES AND TRANSPORT SYSTEMS 2015; 98:371-405. [DOI: 10.1016/bs.vh.2014.12.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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22
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Johnson RT, Breedlove SM, Jordan CL. Androgen receptors mediate masculinization of astrocytes in the rat posterodorsal medial amygdala during puberty. J Comp Neurol 2013; 521:2298-309. [PMID: 23239016 DOI: 10.1002/cne.23286] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Revised: 12/03/2012] [Accepted: 12/11/2012] [Indexed: 11/07/2022]
Abstract
Astrocytes in the posterodorsal portion of the medial amygdala (MePD) are sexually dimorphic in adult rats: males have more astrocytes in the right MePD and more elaborate processes in the left MePD than do females. Functional androgen receptors (ARs) are required for masculinization of MePD astrocytes, as these measures are demasculinized in adult males carrying the testicular feminization mutation (Tfm) of the AR gene, which renders AR dysfunctional. We now report that the number of astrocytes is already sexually dimorphic in the right MePD of juvenile 25-day-old (P25) rats. Because Tfm males have as many astrocytes as wild-type males at this age, this prepubertal sexual dimorphism is independent of ARs. After P25, astrocyte number increases in the MePD of all groups, but activation of ARs augments this increase in the right MePD, where more astrocytes are added in males than in Tfm males. Consequently, by adulthood, females and Tfm males have equivalent numbers of astrocytes in the right MePD. Sexual dimorphism in astrocyte arbor complexity in the left MePD arises after P25, and is entirely AR-dependent. Thus, masculinization of MePD astrocytes is a result of both AR-independent processes before the juvenile period and AR-dependent processes afterward.
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Affiliation(s)
- Ryan T Johnson
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824-1101, USA.
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23
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Steinman MQ, Valenzuela AE, Siopes TD, Millam JR. Tuberal hypothalamic expression of the glial intermediate filaments, glial fibrillary acidic protein and vimentin across the turkey hen (Meleagris gallopavo) reproductive cycle: Further evidence for a role of glial structural plasticity in seasonal reproduction. Gen Comp Endocrinol 2013; 193:141-8. [PMID: 23948371 PMCID: PMC3812377 DOI: 10.1016/j.ygcen.2013.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 08/01/2013] [Accepted: 08/04/2013] [Indexed: 11/25/2022]
Abstract
Glia regulate the hypothalamic-pituitary-gonadal (HPG) axis in birds and mammals. This is accomplished mechanically by ensheathing gonadotrophin-releasing hormone I (GnRH) nerve terminals thereby blocking access to the pituitary blood supply, or chemically in a paracrine manner. Such regulation requires appropriate spatial associations between glia and nerve terminals. Female turkeys (Meleagris gallopavo) use day length as a primary breeding cue. Long days activate the HPG-axis until the hen enters a photorefractory state when previously stimulatory day lengths no longer support HPG-axis activity. Hens must then be exposed to short days before reactivation of the reproductive axis occurs. As adult hens have discrete inactive reproductive states in addition to a fertile state, they are useful for examining the glial contribution to reproductive function. We immunostained tuberal hypothalami from short and long-day photosensitive hens, plus long-day photorefractory hens to examine expression of two intermediate filaments that affect glial morphology: glial fibrillary acidic protein (GFAP) and vimentin. GFAP expression was drastically reduced in the central median eminence of long day photosensitive hens, especially within the internal zone. Vimentin expression was similar among groups. However, vimentin-immunoreactive fibers abutting the portal vasculature were significantly negatively correlated with GFAP expression in the median eminence, which is consistent with our hypothesis for a reciprocal relationship between GFAP and vimentin expression. It appears that up-regulation of GFAP expression in the central median eminence of turkey hens is associated with periods of reproductive quiescence and that photofractoriness is associated with the lack of a glial cytoskeletal response to long days.
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Affiliation(s)
- Michael Q Steinman
- Molecular, Cellular and Integrative Physiology Graduate Group, University of California, Davis, CA 95616, USA; Department of Psychology, University of California, Davis, CA 95616, USA.
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Buckman LB, Thompson MM, Moreno HN, Ellacott KLJ. Regional astrogliosis in the mouse hypothalamus in response to obesity. J Comp Neurol 2013; 521:1322-33. [PMID: 23047490 DOI: 10.1002/cne.23233] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 08/24/2012] [Accepted: 10/02/2012] [Indexed: 11/07/2022]
Abstract
Obesity is associated with chronic low-grade inflammation in peripheral tissues, which contributes to the development of comorbidities such as insulin resistance and cardiovascular disease. While less extensively characterized, obesity also promotes inflammation in the central nervous system (CNS) and the consequences of this inflammation for CNS function are only beginning to be examined. In response to CNS insults such as inflammation, astrocytes undergo a process of hypertrophy and hyperplasia known as reactive astrogliosis. We used immunohistochemistry to examine the differential distribution of the astrocyte marker glial-fibrillary acidic protein (GFAP) in the brains of diet-induced or genetically obese mice compared with their respective lean controls to determine whether different nuclei of the hypothalamus showed comparable astrogliosis in response to obesity. The areas that showed the highest differential GFAP immunoreactivity between lean and obese animals include the medial preoptic, paraventricular, and dorsomedial nuclei. Comparatively, little astrogliosis was seen in the ventromedial nucleus, lateral hypothalamus, or anterior hypothalamic area. In obese animals high levels of GFAP immunoreactivity were often associated with the microvasculature. There were no differences in the differential distribution of GFAP staining between obese animals and their lean controls in the diet-induced compared with the genetic model of obesity. The exact cause(s) of the astrogliosis in obesity is not known. The finding that obesity causes a distinct pattern of elevated GFAP immunoreactivity associated with microvessels suggests that the astrogliosis may be occurring as a response to changes at the blood-brain barrier and/or in the peripheral circulation.
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Affiliation(s)
- Laura B Buckman
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee 37232-0615, USA
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Lizarbe B, Benitez A, Peláez Brioso GA, Sánchez-Montañés M, López-Larrubia P, Ballesteros P, Cerdán S. Hypothalamic metabolic compartmentation during appetite regulation as revealed by magnetic resonance imaging and spectroscopy methods. FRONTIERS IN NEUROENERGETICS 2013; 5:6. [PMID: 23781199 PMCID: PMC3680712 DOI: 10.3389/fnene.2013.00006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Accepted: 05/28/2013] [Indexed: 12/14/2022]
Abstract
We review the role of neuroglial compartmentation and transcellular neurotransmitter cycling during hypothalamic appetite regulation as detected by Magnetic Resonance Imaging (MRI) and Spectroscopy (MRS) methods. We address first the neurochemical basis of neuroendocrine regulation in the hypothalamus and the orexigenic and anorexigenic feed-back loops that control appetite. Then we examine the main MRI and MRS strategies that have been used to investigate appetite regulation. Manganese-enhanced magnetic resonance imaging (MEMRI), Blood oxygenation level-dependent contrast (BOLD), and Diffusion-weighted magnetic resonance imaging (DWI) have revealed Mn2+ accumulations, augmented oxygen consumptions, and astrocytic swelling in the hypothalamus under fasting conditions, respectively. High field 1H magnetic resonance in vivo, showed increased hypothalamic myo-inositol concentrations as compared to other cerebral structures. 1H and 13C high resolution magic angle spinning (HRMAS) revealed increased neuroglial oxidative and glycolytic metabolism, as well as increased hypothalamic glutamatergic and GABAergic neurotransmissions under orexigenic stimulation. We propose here an integrative interpretation of all these findings suggesting that the neuroendocrine regulation of appetite is supported by important ionic and metabolic transcellular fluxes which begin at the tripartite orexigenic clefts and become extended spatially in the hypothalamus through astrocytic networks becoming eventually MRI and MRS detectable.
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Affiliation(s)
- Blanca Lizarbe
- Department of Experimental Models of Human diseases, Laboratory of Imaging and Spectroscopy by Magnetic Resonance, Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC/UAM Madrid, Spain
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Pubertally born neurons and glia are functionally integrated into limbic and hypothalamic circuits of the male Syrian hamster. Proc Natl Acad Sci U S A 2013; 110:4792-7. [PMID: 23460698 DOI: 10.1073/pnas.1219443110] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
During puberty, the brain goes through extensive remodeling, involving the addition of new neurons and glia to brain regions beyond the canonical neurogenic regions (i.e., dentate gyrus and olfactory bulb), including limbic and hypothalamic cell groups associated with sex-typical behavior. Whether these pubertally born cells become functionally integrated into neural circuits remains unknown. To address this question, we gave male Syrian hamsters daily injections of the cell birthdate marker bromodeoxyuridine throughout puberty (postnatal day 28-49). Half of the animals were housed in enriched environments with access to a running wheel to determine whether enrichment increased the survival of pubertally born cells compared with the control environment. At 4 wk after the last BrdU injection, animals were allowed to interact with a receptive female and were then killed 1 h later. Triple-label immunofluorescence for BrdU, the mature neuron marker neuronal nuclear antigen, and the astrocytic marker glial fibrillary acidic protein revealed that a proportion of pubertally born cells in the medial preoptic area, arcuate nucleus, and medial amygdala differentiate into either mature neurons or astrocytes. Double-label immunofluorescence for BrdU and the protein Fos revealed that a subset of pubertally born cells in these regions is activated during sociosexual behavior, indicative of their functional incorporation into neural circuits. Enrichment affected the survival and activation of pubertally born cells in a brain region-specific manner. These results demonstrate that pubertally born cells located outside of the traditional neurogenic regions differentiate into neurons and glia and become functionally incorporated into neural circuits that subserve sex-typical behaviors.
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Geller S, Kolasa E, Tillet Y, Duittoz A, Vaudin P. Olfactory ensheathing cells form the microenvironment of migrating GnRH-1 neurons during mouse development. Glia 2013; 61:550-66. [PMID: 23404564 DOI: 10.1002/glia.22455] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 11/28/2012] [Indexed: 11/08/2022]
Abstract
During development, GnRH-1 neurons differentiate extracerebraly from the nasal placode and migrate from the vomeronasal organ to the forebrain along vomeronasal and terminal nerves. Numerous studies have described the influence of different molecules on the migration of GnRH-1 neurons, however, the role of microenvironment cells remains poorly understood. This study used GFAP-GFP transgenic mice to detect glial cells at early developmental stages. Using nasal explant cultures, the comigration of glial cells with GnRH-1 neurons was clearly demonstrated. This in vitro approach showed that glial cells began migrating from the explants before GnRH-1 neurons. They remained ahead of the GnRH-1 migratory front and stopped migrating after the GnRH-1 neurons. The association of these glial cells with the axons combined with gene expression analysis of GFAP-GFP sorted cells enabled them to be identified as olfactory ensheathing cells (OEC). Immunohistochemical analysis revealed the presence of multiple glial cell-type markers showing several OEC subpopulations surrounding GnRH-1 neurons. Moreover, these OEC expressed genes whose products are involved in the migration of GnRH-1 neurons, such as Nelf and Semaphorin 4. In situ data confirmed that the majority of the GnRH-1 neurons were associated with glial cells along the vomeronasal axons in nasal septum and terminal nerves in the nasal forebrain junction as early as E12.5. Overall, these data demonstrate an OEC microenvironment for migrating GnRH-1 neurons during mouse development. The fact that this glial cell type precedes GnRH-1 neurons and encodes for molecules involved in their nasal migration suggests that it participates in the GnRH-1 system ontogenesis.
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Affiliation(s)
- Sarah Geller
- Physiologie de la Reproduction et des Comportements, UMR 0085 INRA, 6175 CNRS, Université François Rabelais de Tours, IFCE, IFR135 Imagerie Fonctionnelle 37380, Nouzilly, France
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Sharif A, Baroncini M, Prevot V. Role of glia in the regulation of gonadotropin-releasing hormone neuronal activity and secretion. Neuroendocrinology 2013; 98:1-15. [PMID: 23735672 DOI: 10.1159/000351867] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 05/08/2013] [Indexed: 11/19/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) neurons are the final common pathway for the central control of reproduction. The coordinated and timely activation of these hypothalamic neurons, which determines sexual development and adult reproductive function, lies under the tight control of a complex array of excitatory and inhibitory transsynaptic inputs. In addition, research conducted over the past 20 years has unveiled the major contribution of glial cells to the control of GnRH neurons. Glia use a variety of molecular and cellular strategies to modulate GnRH neuronal function both at the level of their cell bodies and at their nerve terminals. These mechanisms include the secretion of bioactive molecules that exert paracrine effects on GnRH neurons, juxtacrine interactions between glial cells and GnRH neurons via adhesive molecules and the morphological plasticity of the glial coverage of GnRH neurons. It now appears that glial cells are integral components, along with upstream neuronal networks, of the central control of GnRH neuronal function. This review attempts to summarize our current knowledge of the mechanisms used by glial cells to control GnRH neuronal activity and secretion.
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Affiliation(s)
- Ariane Sharif
- INSERM, Jean-Pierre Aubert Research Center, Development and Plasticity of the Postnatal Brain, Unit 837, and UDSL, School of Medicine, Lille, France.
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29
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Fuente-Martín E, García-Cáceres C, Granado M, de Ceballos ML, Sánchez-Garrido MÁ, Sarman B, Liu ZW, Dietrich MO, Tena-Sempere M, Argente-Arizón P, Díaz F, Argente J, Horvath TL, Chowen JA. Leptin regulates glutamate and glucose transporters in hypothalamic astrocytes. J Clin Invest 2012; 122:3900-13. [PMID: 23064363 DOI: 10.1172/jci64102] [Citation(s) in RCA: 155] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 08/27/2012] [Indexed: 01/08/2023] Open
Abstract
Glial cells perform critical functions that alter the metabolism and activity of neurons, and there is increasing interest in their role in appetite and energy balance. Leptin, a key regulator of appetite and metabolism, has previously been reported to influence glial structural proteins and morphology. Here, we demonstrate that metabolic status and leptin also modify astrocyte-specific glutamate and glucose transporters, indicating that metabolic signals influence synaptic efficacy and glucose uptake and, ultimately, neuronal function. We found that basal and glucose-stimulated electrical activity of hypothalamic proopiomelanocortin (POMC) neurons in mice were altered in the offspring of mothers fed a high-fat diet. In adulthood, increased body weight and fasting also altered the expression of glucose and glutamate transporters. These results demonstrate that whole-organism metabolism alters hypothalamic glial cell activity and suggest that these cells play an important role in the pathology of obesity.
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Affiliation(s)
- Esther Fuente-Martín
- Hospital Infantil Universitario Niño Jesús, Department of Endocrinology, Instituto de Investigación La Princesa, Madrid, Spain
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30
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Witham EA, Meadows JD, Shojaei S, Kauffman AS, Mellon PL. Prenatal exposure to low levels of androgen accelerates female puberty onset and reproductive senescence in mice. Endocrinology 2012; 153:4522-32. [PMID: 22778229 PMCID: PMC3423623 DOI: 10.1210/en.2012-1283] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sex steroid hormone production and feedback mechanisms are critical components of the hypothalamic-pituitary-gonadal (HPG) axis and regulate fetal development, puberty, fertility, and menopause. In female mammals, developmental exposure to excess androgens alters the development of the HPG axis and has pathophysiological effects on adult reproductive function. This study presents an in-depth reproductive analysis of a murine model of prenatal androgenization (PNA) in which females are exposed to a low dose of dihydrotestosterone during late prenatal development on embryonic d 16.5-18.5. We determined that PNA females had advanced pubertal onset and a delay in the time to first litter, compared with vehicle-treated controls. The PNA mice also had elevated testosterone, irregular estrous cyclicity, and advanced reproductive senescence. To assess the importance of the window of androgen exposure, dihydrotestosterone was administered to a separate cohort of female mice on postnatal d 21-23 [prepubertal androgenization (PPA)]. PPA significantly advanced the timing of pubertal onset, as observed by age of the vaginal opening, yet had no effects on testosterone or estrous cycling in adulthood. The absence of kisspeptin receptor in Kiss1r-null mice did not change the acceleration of puberty by the PNA and PPA paradigms, indicating that kisspeptin signaling is not required for androgens to advance puberty. Thus, prenatal, but not prepubertal, exposure to low levels of androgens disrupts normal reproductive function throughout life from puberty to reproductive senescence.
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Affiliation(s)
- Emily A Witham
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093, USA
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31
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Ouyang H, Liu S, Zeng W, Levitt RC, Candiotti KA, Hao S. An emerging new paradigm in opioid withdrawal: a critical role for glia-neuron signaling in the periaqueductal gray. ScientificWorldJournal 2012; 2012:940613. [PMID: 22919361 PMCID: PMC3419410 DOI: 10.1100/2012/940613] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 06/06/2012] [Indexed: 11/25/2022] Open
Abstract
The chronic use of opiates (i.e., narcotics such as the natural derivatives of opium including morphine or codeine) or opioids (i.e., semisynthetic derivatives of opium and other molecules that activate opioid receptors) induces dependence, which is associated with various specific behavioral and somatic signs after their withdrawal or after the administration of an opioid antagonist. Among the brain regions implicated in opiate dependence and withdrawal, the periaqueductal gray area (PAG) appears to be critical in regulating the complex signs and symptoms of opioid withdrawal. Numerous neurochemical mechanisms in the PAG have been identified that may contribute to the opioid withdrawal syndrome. Accumulating evidence suggests that glial activation leading to the release of proinflammatory molecules acting on neurons is important in the complex syndrome of opioid dependence and withdrawal. This paper focuses on the recent advances in our understanding of the vital role that glia-neuron interactions play in opioid dependence and withdrawal within the PAG. We summarize those neurochemical mechanisms associated with opioid withdrawal including the recently defined importance of TNFα release from activated glial cells that communicate with TNF receptors on PAG neurons.
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Affiliation(s)
- Handong Ouyang
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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32
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Johnson RT, Schneider A, DonCarlos LL, Breedlove SM, Jordan CL. Astrocytes in the rat medial amygdala are responsive to adult androgens. J Comp Neurol 2012; 520:2531-44. [PMID: 22581688 PMCID: PMC4209966 DOI: 10.1002/cne.23061] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The posterodorsal medial amygdala (MePD) exhibits numerous sex differences including differences in volume and in the number and morphology of neurons and astroctyes. In adulthood, gonadal hormones, including both androgens and estrogens, have been shown to play a role in maintaining the masculine character of many of these sex differences, but whether adult gonadal hormones maintain the increased number and complexity of astrocytes in the male MePD was unknown. To answer this question we examined astrocytes in the MePD of male and female Long Evans rats that were gonadectomized as adults and treated for 30 days with either testosterone or a control treatment. At the end of treatment brains were collected and immunostained for glial fibrillary acidic protein. Stereological analysis revealed that adult androgen levels influenced the number and complexity of astrocytes in the MePD of both sexes, but the specific effects of androgens were different in males and females. However, sex differences in the number and complexity of adult astrocytes persisted even in the absence of gonadal hormones in adulthood, suggesting that androgens also act earlier in life to determine these adult sex differences. Using immunofluorescence and confocal microscopy, we found robust androgen receptor immunostaining in a subpopulation of MePD astrocytes, suggesting that testosterone may act directly on MePD astrocytes to influence their structure and function.
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Affiliation(s)
- Ryan T Johnson
- Neuroscience Program, Michigan State University, East Lansing, Michigan 48824-1101, USA.
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33
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Changes in the Level of Neuronal Cell Adhesion Molecule in the Brain of Male Rats under Conditions of Suppression of Production of Testosterone. NEUROPHYSIOLOGY+ 2012. [DOI: 10.1007/s11062-012-9270-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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34
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Girardet C, Bosler O. [Structural plasticity of the adult central nervous system: insights from the neuroendocrine hypothalamus]. Biol Aujourdhui 2011; 205:179-97. [PMID: 21982406 DOI: 10.1051/jbio/2011018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Indexed: 01/26/2023]
Abstract
Accumulating evidence renders the dogma obsolete according to which the structural organization of the brain would remain essentially stable in adulthood, changing only in response to a need for compensatory processes during increasing age and degeneration. It has indeed become clear from investigations on various models that the adult nervous system can adapt to physiological demands by altering reversibly its synaptic circuits. This potential for structural and functional modifications results not only from the plastic properties of neurons but also from the inherent capacity of the glial cellular components to undergo remodeling as well. This is currently known for astrocytes, the major glial cells in brain which are well-recognized as dynamic partners in the mechanisms of synaptic transmission, and for the tanycytes and pituicytes which contribute to the regulation of neurosecretory processes in neurohemal regions of the hypothalamus. Studies on the neuroendocrine hypothalamus, whose role is central in homeostatic regulations, have gained good insights into the spectacular neuronal-glial rearrangements that may subserve functional plasticity in the adult brain. Following pioneering works on the morphological reorganizations taking place in the hypothalamo-neurohypophyseal system under certain physiological conditions such as dehydration and lactation, studies on the gonadotropic system that orchestrates reproductive functions have re-emphasized the dynamic interplay between neurons and glia in brain structural plasticity processes. This review summarizes the major contributions provided by these researches in the field and also addresses the question of the morphological rearrangements that occur on a 24-h basis in the central component of the circadian clock responsible for the temporal aspects of endocrine regulations. Taken together, the reviewed data highlight the close cooperation between neurons and glia in developing strategies for functional adaptation of the brain to the changing conditions of the internal and external environment.
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Affiliation(s)
- Clémence Girardet
- Centre de Recherche en Neurobiologie-Neurophysiologie de Marseille, France.
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35
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Melcangi R, Panzica G, Garcia-Segura L. Neuroactive steroids: focus on human brain. Neuroscience 2011; 191:1-5. [DOI: 10.1016/j.neuroscience.2011.06.024] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 06/04/2011] [Accepted: 06/07/2011] [Indexed: 10/18/2022]
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36
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Salmaso N, Quinlan MG, Brake WG, Woodside B. Changes in dendritic spine density on layer 2/3 pyramidal cells within the cingulate cortex of late pregnant and postpartum rats. Horm Behav 2011; 60:65-71. [PMID: 21397603 DOI: 10.1016/j.yhbeh.2011.03.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Revised: 02/28/2011] [Accepted: 03/03/2011] [Indexed: 01/26/2023]
Abstract
A rapid upregulation of astrocytic protein expression within area 2 of the cingulate cortex (Cg2) of the maternal rat occurs within 3h postpartum and persists throughout lactation. Previous studies have shown that similar changes in astrocytic proteins can signal changes in local synapses and dendritic spines. Thus, here we used the Golgi-Cox impregnation technique to compare spine density in layer 2 and 3 pyramidal cells of Cg2, the CA1 region of the hippocampus and the parietal cortex (ParCx) among metestrus, late pregnant (LP), 3-hour postpartum (3H PP) and 16-day postpartum rats (D16 PP). Rats in the 3H PP group had higher numbers of dendritic spines/10 μm on the apical dendrites of pyramidal neurons in both Cg2 and CA1 than the other groups, which did not differ. A similar pattern was observed in basilar dendrites but this failed to reach significance. In Cg2, Sholl analysis revealed that rats in the D16 PP group had a significantly greater extent of dendritic arborization in the basilar region than any other group. These data suggest that the changes in astrocytic proteins that occur in Cg2 in the postpartum period are associated with neuronal plasticity in pyramidal layers 2 and 3.
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Affiliation(s)
- N Salmaso
- CSBN/GRNC, Concordia University, 7141 Sherbrooke St. W., Montreal, Quebec, Canada H4B 1R6
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37
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Abstract
In the twentieth century, the dominant model of sexual differentiation stated that genetic sex (XX versus XY) causes differentiation of the gonads, which then secrete gonadal hormones that act directly on tissues to induce sex differences in function. This serial model of sexual differentiation was simple, unifying and seductive. Recent evidence, however, indicates that the linear model is incorrect and that sex differences arise in response to diverse sex-specific signals originating from inherent differences in the genome and involve cellular mechanisms that are specific to individual tissues or brain regions. Moreover, sex-specific effects of the environment reciprocally affect biology, sometimes profoundly, and must therefore be integrated into a realistic model of sexual differentiation. A more appropriate model is a parallel-interactive model that encompasses the roles of multiple molecular signals and pathways that differentiate males and females, including synergistic and compensatory interactions among pathways and an important role for the environment.
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Affiliation(s)
- Margaret M McCarthy
- Departments of Physiology and Psychiatry and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, USA.
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38
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Wyszyńska-Koko J, de Wit AAC, Beerda B, Veerkamp RF, te Pas MFW. Gene expression patterns in the ventral tegmental area relate to oestrus behaviour in high-producing dairy cows. J Anim Breed Genet 2011; 128:183-91. [PMID: 21554412 DOI: 10.1111/j.1439-0388.2010.00915.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Reduced oestrus behaviour expression or its absence (silent oestrus) results in subfertility in high-producing dairy cows. Insight into the genomic regulation of oestrus behaviour is likely to help alleviate reproduction problems. Here, gene expression was recorded in the ventral tegmental area (VTA) of high milk production dairy cows differing in the degree of showing oestrus behaviour (H - highly expressing versus L - lowly expressing), which was then analysed. Genes regulating cell morphology and adhesion or coding for immunoglobulin G (IgG) chains were differentially expressed in VTA between cows around day 0 and 12 of the oestrus cycle, but only in cows that earlier in life tended to show high levels of oestrus behaviour (H0 versus H12). The comparisons between H and L groups of cows also revealed differential expression of several genes (e.g. those of the IgG family or encoding for pro-melanin-concentrating hormone). However, any significant changes in VTA genes expression were detected in the comparison of L0 versus L12 cows. Altogether, the genes expression profile in VTA of cows highly expressing oestrus behaviour changes together with phases of the oestrus cycle, while in case of cows expressing oestrus behaviour lowly it remains stable. This supports the existence of genomic regulation by centrally expressed genes on the expression of oestrus behaviour in dairy cows.
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Affiliation(s)
- J Wyszyńska-Koko
- Institute of Genetics and Animal Breeding, Polish Academy of Sciences, Jastrzębiec, Wólka Kosowska, Poland.
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39
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Lenz KM, McCarthy MM. Organized for sex - steroid hormones and the developing hypothalamus. Eur J Neurosci 2011; 32:2096-104. [PMID: 21143664 DOI: 10.1111/j.1460-9568.2010.07511.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Steroid hormones of gonadal origin act on the neonatal brain, particularly the hypothalamus, to produce sex differences that underlie copulatory behavior. Neuroanatomical sex differences include regional volume, cell number, connectivity, morphology, physiology, neurotransmitter phenotype and molecular signaling, all of which are determined by the action of steroid hormones, particularly by estradiol in males, and are established by diverse downstream effects. Sex differences in distinct hypothalamic regions can be organized by the same steroid hormone, but the direction of a sex difference is often specific to one region or cell type, illustrating the wide range of effects that steroid hormones have on the developing brain. Substantial progress has been made in elucidating the downstream mechanisms through which gonadal hormones sexually differentiate the brain, but gaps remain in establishing the precise relationship between changes in neuronal morphology and behavior. A complete understanding of sexual differentiation will require integrating the diverse mechanisms across multiple brain regions into a functional network that regulates behavioral output.
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Affiliation(s)
- Kathryn M Lenz
- Department of Physiology and Program in Neuroscience, School of Medicine, University of Maryland, Baltimore, MD 21201, USA.
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40
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Gonzalez B, Ratner LD, Di Giorgio NP, Poutanen M, Huhtaniemi IT, Calandra RS, Lux-Lantos VAR, Rulli SB. Endogenously elevated androgens alter the developmental programming of the hypothalamic-pituitary axis in male mice. Mol Cell Endocrinol 2011; 332:78-87. [PMID: 20933053 DOI: 10.1016/j.mce.2010.09.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 09/14/2010] [Accepted: 09/28/2010] [Indexed: 01/09/2023]
Abstract
Transgenic male mice that express human chorionic gonadotropin (hCG) α and β subunits constitutively hypersecrete hCG and produce elevated levels of androgens. The aim of this study was to characterize the hypothalamic-pituitary function of these transgenic (hCGαβ+) males by focusing on FSH regulation. Serum FSH levels and pituitary mRNA expression of Fshb, Lhb, Cga, Gnrhr and Esr1 were reduced, whereas Fst expression was increased in prepubertal hCGαβ+ males as compared with wild-type. In the hypothalamus, Cyp19a1 expression, GnRH concentration and ex-vivo GnRH pulsatility were elevated in prepubertal hCGαβ+ mice, whereas Kiss1 expression was decreased prepubertally and Gad67 expression was elevated neonatally. The effect of androgens on the developmental programming of the hypothalamic-pituitary axis of hCGαβ+ males was evaluated by perinatal and prepubertal antiandrogen (flutamide) administration. Our studies identified a critical window between gestational day 18 and postnatal day 14, during which chronically elevated androgens and/or their locally produced metabolites activate the hypothalamus and concomitantly shut-down the gonadotropin axis.
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Affiliation(s)
- Betina Gonzalez
- Instituto de Biología y Medicina Experimental-CONICET, Vuelta de Obligado 2490 (1428), Buenos Aires, Argentina
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41
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Bellefontaine N, Hanchate NK, Parkash J, Campagne C, de Seranno S, Clasadonte J, d'Anglemont de Tassigny X, Prevot V. Nitric oxide as key mediator of neuron-to-neuron and endothelia-to-glia communication involved in the neuroendocrine control of reproduction. Neuroendocrinology 2011; 93:74-89. [PMID: 21335953 DOI: 10.1159/000324147] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Accepted: 01/04/2011] [Indexed: 01/22/2023]
Abstract
Nitric oxide (NO) is a peculiar chemical transmitter that freely diffuses through aqueous and lipid environments and plays a role in major aspects of brain function. Within the hypothalamus, NO exerts critical effects upon the gonadotropin-releasing hormone (GnRH) network to maintain fertility. Here, we review recent evidence that NO regulates major aspects of the GnRH neuron physiology. Far more active than once thought, NO powerfully controls GnRH neuronal activity, GnRH release and structural plasticity at the neurohemal junction. In the preoptic region, neuronal nitric oxide synthase (nNOS) activity is tightly regulated by estrogens and is found to be maximal at the proestrus stage. Natural fluctuations of estrogens control both the differential coupling of this Ca²+-activated enzyme to glutamate N-methyl-D-aspartic acid receptor channels and phosphorylation-mediated nNOS activation. Furthermore, NO endogenously produced by neurons expressing nNOS acutely and directly suppresses spontaneous firing in GnRH neurons, which suggests that neuronal NO may serve as a synchronizing switch within the preoptic region. At the median eminence, NO is spontaneously released from an endothelial source and follows a pulsatile and cyclic pattern of secretion. Importantly, GnRH release appears to be causally related to endothelial NO release. NO is also highly involved in mediating the dialogue set in motion between vascular endothelial cells and tanycytes that control the direct access of GnRH neurons to the pituitary portal blood during the estrous cycle. Altogether, these data raise the intriguing possibility that the neuroendocrine brain uses NO to coordinate both GnRH neuronal activity and GnRH release at key stages of reproductive physiology.
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Affiliation(s)
- Nicole Bellefontaine
- Inserm, Jean-Pierre Aubert Research Center, Development and Plasticity of the Postnatal Brain, U837, Lille, France
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42
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Azcoitia I, Santos-Galindo M, Arevalo MA, Garcia-Segura LM. Role of astroglia in the neuroplastic and neuroprotective actions of estradiol. Eur J Neurosci 2010; 32:1995-2002. [DOI: 10.1111/j.1460-9568.2010.07516.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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43
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García-Cáceres C, Lagunas N, Calmarza-Font I, Azcoitia I, Diz-Chaves Y, García-Segura LM, Baquedano E, Frago LM, Argente J, Chowen JA. Gender differences in the long-term effects of chronic prenatal stress on the HPA axis and hypothalamic structure in rats. Psychoneuroendocrinology 2010; 35:1525-35. [PMID: 20558007 DOI: 10.1016/j.psyneuen.2010.05.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2009] [Revised: 04/19/2010] [Accepted: 05/20/2010] [Indexed: 11/26/2022]
Abstract
Stress during pregnancy can impair biological and behavioral responses in the adult offspring and some of these effects are associated with structural changes in specific brain regions. Furthermore, these outcomes can vary according to strain, gender, and type and duration of the maternal stress. Indeed, early stress can induce sexually dimorphic long-term effects on diverse endocrine axes, including subsequent responses to stress. However, whether hypothalamic structural modifications are associated with these endocrine disruptions has not been reported. Thus, we examined the gender differences in the long-term effects of prenatal and adult immobilization stress on the hypothalamic-pituitary-adrenocortical (HPA) axis and the associated changes in hypothalamic structural proteins. Pregnant Wistar rats were subjected to immobilization stress three times daily (45 min each) during the last week of gestation. One half of the offspring were subjected to the same regimen of stress on 10 consecutive days starting at postnatal day (PND) 90. At sacrifice (PND 180), serum corticosterone levels were significantly higher in females compared to males and increased significantly in females subjected to both stresses with no change in males. Prenatal stress increased pituitary ACTH content in males, with no effect in females. Hypothalamic CRH mRNA levels were significantly increased by prenatal stress in females, but decreased in male rats. In females neither stress affected hypothalamic cell death, as determined by cytoplasmic histone-associated DNA fragment levels or proliferation, determined by proliferating cell nuclear antigen levels (PCNA); however, in males there was a significant decrease in cell death in response to prenatal stress and a decrease in PCNA levels with both prenatal and adult stress. In all groups BrdU immunoreactivity colocalized in glial fibrillary acidic protein (GFAP) positive cells, with few BrdU/NeuN labelled cells found. Furthermore, in males the astrocyte marker S100β increased with prenatal stress and decreased with adult stress, suggesting affectation of astrocytes. Synapsin-1 levels were increased by adult stress in females and by prenatal stress in males, while, PSD95 levels were increased in females and decreased in males by both prenatal and adult stress. In conclusion, hypothalamic structural rearrangement appears to be involved in the long-term endocrine outcomes observed after both chronic prenatal and adult stresses. Furthermore, many of these changes are not only different between males and females, but opposite, which could underlie the gender differences in the long-term sequelae of chronic stress, including subsequent responses to stress.
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Affiliation(s)
- Cristina García-Cáceres
- Hospital Infantil Universitario Niño Jesús, Universidad Autónoma de Madrid, CIBER Fisiopatología de Obesidad y Nutrición (CIBERobn), Instituto de Salud Carlos III, Madrid 28009, Spain
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Actions of estrogens on glial cells: Implications for neuroprotection. Biochim Biophys Acta Gen Subj 2010; 1800:1106-12. [DOI: 10.1016/j.bbagen.2009.10.002] [Citation(s) in RCA: 148] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 09/29/2009] [Accepted: 10/01/2009] [Indexed: 01/21/2023]
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Cyr NE, Kua LH, Bruce LA, Chadwick JG, Tetel MJ, Wolfson AJ. Nuclear Thimet oligopeptidase is coexpressed with oestrogen receptor alpha in hypothalamic cells and regulated by oestradiol in female mice. J Neuroendocrinol 2010; 22:936-43. [PMID: 20456597 PMCID: PMC2921797 DOI: 10.1111/j.1365-2826.2010.02009.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Thimet oligopeptidase (EC 3.4.24.15; also called EP24.15 and TOP; referred to here as TOP) is a neuropeptidase involved in the regulation of several physiological functions including reproduction. Among its substrates is gonadotrophin-releasing hormone (GnRH), an important hypothalamic hormone that regulates the synthesis and release of oestradiol and facilitates female sexual behaviour. Using immunohistochemistry, we found that TOP is expressed in the nucleus of cells throughout the female mouse brain, and in high levels in steroid-sensitive regions of the hypothalamus, which is consistent with previous findings in male rats. Furthermore, dual-label immunofluorescence revealed that TOP and oestrogen receptor alpha (ERalpha) coexpress in several reproductively-relevant brain regions, including the medial preoptic area (mPOA), arcuate nucleus (ARC), ventrolateral portion of the ventromedial hypothalamic nucleus (VMNvl) and the midbrain central grey (MCG). Previous studies in rats have shown that oestradiol decreases hypothalamic TOP levels or activity, possibly potentiating the effects of GnRH. In the present study, analysis by immunohistochemistry revealed that oestradiol decreased TOP immunoreactivity in the VMNvl, whereas no differences were detected in the mPOA, ARC or median eminence. Overall, the present findings indicate that TOP is coexpressed with ERalpha, and oestradiol regulates TOP expression in a brain region-specific manner in female mice, providing neuroanatomical evidence that TOP may function in reproductive physiology and/or behaviour.
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Affiliation(s)
- N E Cyr
- Chemistry Department, Wellesley College, Wellesley, MA 02481-8203, USA
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Prevot V, Bellefontaine N, Baroncini M, Sharif A, Hanchate NK, Parkash J, Campagne C, de Seranno S. Gonadotrophin-releasing hormone nerve terminals, tanycytes and neurohaemal junction remodelling in the adult median eminence: functional consequences for reproduction and dynamic role of vascular endothelial cells. J Neuroendocrinol 2010; 22:639-49. [PMID: 20492366 PMCID: PMC3168864 DOI: 10.1111/j.1365-2826.2010.02033.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Although coordinated actions of several areas within the hypothalamus are involved in the secretion of gonadotrophin-releasing hormone (GnRH), the median eminence of the hypothalamus, where the nerve terminals are located, plays a particularly critical role in the release of GnRH. In adult females, prior to the preovulatory surge of GnRH, the retraction of specialised ependymoglial cells lining the floor of the third ventricle named tanycytes allows for the juxtaposition of GnRH nerve terminals with the adjacent pericapillary space of the pituitary portal vasculature, thus forming direct neurohaemal junctions. These morphological changes occur within a few hours and are reversible. Such remodelling may promote physiological conditions to enhance the central release of GnRH and potentiate oestrogen-activated GnRH release. This plasticity involves dynamic cell interactions that bring into play tanycytes, astrocytes, vascular endothelial cells and GnRH neurones themselves. The underlying signalling pathways responsible for these structural changes are comprised of highly diffusible gaseous molecules, such as endothelial nitric oxide, and paracrine communication processes involving receptors of the erbB tyrosine kinase family, transforming growth factor beta 1 and eicosanoids, such as prostaglandin E(2). Some of these molecules, as a result of their ability to diffuse within the median eminence, may also serve as synchronizing cues allowing for the occurrence of functionally meaningful episodes of GnRH secretion by coordinating GnRH release from the GnRH neuroendocrine terminals.
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Affiliation(s)
- V Prevot
- Inserm, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, Lille, France.
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Prevot V, Hanchate NK, Bellefontaine N, Sharif A, Parkash J, Estrella C, Allet C, de Seranno S, Campagne C, de Tassigny XD, Baroncini M. Function-related structural plasticity of the GnRH system: a role for neuronal-glial-endothelial interactions. Front Neuroendocrinol 2010; 31:241-58. [PMID: 20546773 DOI: 10.1016/j.yfrne.2010.05.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 05/17/2010] [Accepted: 05/18/2010] [Indexed: 12/18/2022]
Abstract
As the final common pathway for the central control of gonadotropin secretion, GnRH neurons are subjected to numerous regulatory homeostatic and external factors to achieve levels of fertility appropriate to the organism. The GnRH system thus provides an excellent model in which to investigate the complex relationships between neurosecretion, morphological plasticity and the expression of a physiological function. Throughout the reproductive cycle beginning from postnatal sexual development and the onset of puberty to reproductive senescence, and even within the ovarian cycle itself, all levels of the GnRH system undergo morphological plasticity. This structural plasticity within the GnRH system appears crucial to the timely control of reproductive competence within the individual, and as such must have coordinated actions of multiple signals secreted from glial cells, endothelial cells, and GnRH neurons. Thus, the GnRH system must be viewed as a complete neuro-glial-vascular unit that works in concert to maintain the reproductive axis.
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Affiliation(s)
- Vincent Prevot
- Inserm, Jean-Pierre Aubert Research Center, U837, Development and Plasticity of the Postnatal Brain, F-59000 Lille, France.
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Gillies GE, McArthur S. Estrogen actions in the brain and the basis for differential action in men and women: a case for sex-specific medicines. Pharmacol Rev 2010; 62:155-98. [PMID: 20392807 PMCID: PMC2879914 DOI: 10.1124/pr.109.002071] [Citation(s) in RCA: 467] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The classic view of estrogen actions in the brain was confined to regulation of ovulation and reproductive behavior in the female of all mammalian species studied, including humans. Burgeoning evidence now documents profound effects of estrogens on learning, memory, and mood as well as neurodevelopmental and neurodegenerative processes. Most data derive from studies in females, but there is mounting recognition that estrogens play important roles in the male brain, where they can be generated from circulating testosterone by local aromatase enzymes or synthesized de novo by neurons and glia. Estrogen-based therapy therefore holds considerable promise for brain disorders that affect both men and women. However, as investigations are beginning to consider the role of estrogens in the male brain more carefully, it emerges that they have different, even opposite, effects as well as similar effects in male and female brains. This review focuses on these differences, including sex dimorphisms in the ability of estradiol to influence synaptic plasticity, neurotransmission, neurodegeneration, and cognition, which, we argue, are due in a large part to sex differences in the organization of the underlying circuitry. There are notable sex differences in the incidence and manifestations of virtually all central nervous system disorders, including neurodegenerative disease (Parkinson's and Alzheimer's), drug abuse, anxiety, and depression. Understanding the cellular and molecular basis of sex differences in brain physiology and responses to estrogen and estrogen mimics is, therefore, vitally important for understanding the nature and origins of sex-specific pathological conditions and for designing novel hormone-based therapeutic agents that will have optimal effectiveness in men or women.
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Affiliation(s)
- Glenda E Gillies
- Centre for Neuroscience, Department of Medicine, Hammersmith Hospital, Imperial College Faculty of Medicine, DuCane Road, London W12ONN, UK.
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Suárez J, Romero-Zerbo SY, Rivera P, Bermúdez-Silva FJ, Pérez J, De Fonseca FR, Fernández-Llebrez P. Endocannabinoid system in the adult rat circumventricular areas: An immunohistochemical study. J Comp Neurol 2010; 518:3065-85. [DOI: 10.1002/cne.22382] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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