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Plumb AN, Lesnak JB, Kolling LJ, Marcinkiewcz CA, Sluka KA. Local Synthesis of Estradiol in the Rostral Ventromedial Medulla Protects against Widespread Muscle Pain in Male Mice. eNeuro 2024; 11:ENEURO.0332-24.2024. [PMID: 39111835 PMCID: PMC11360981 DOI: 10.1523/eneuro.0332-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2024] [Accepted: 07/25/2024] [Indexed: 08/30/2024] Open
Abstract
Animal studies consistently demonstrate that testosterone is protective against pain in multiple models, including an animal model of activity-induced muscle pain. In this model, females develop widespread muscle hyperalgesia, and reducing testosterone levels in males results in widespread muscle hyperalgesia. Widespread pain is believed to be mediated by changes in the central nervous system, including the rostral ventromedial medulla (RVM). The enzyme that converts testosterone to estradiol, aromatase, is highly expressed in the RVM. Therefore, we hypothesized that testosterone is converted by aromatase to estradiol locally in the RVM to prevent development of widespread muscle hyperalgesia in male mice. This was tested through pharmacological inhibition of estrogen receptors (ERs), aromatase, or ER-α in the RVM which resulted in contralateral hyperalgesia in male mice (C57BL/6J). ER inhibition in the RVM had no effect on hyperalgesia in female mice. As prior studies show modulation of estradiol signaling alters GABA receptor and transporter expression, we examined if removal of testosterone in males would decrease mRNA expression of GABA receptor subunits and vesicular GABA transporter (VGAT). However, there were no differences in mRNA expression of GABA receptor subunits of VGAT between gonadectomized and sham control males. Lastly, we used RNAscope to determine expression of ER-α in the RVM and show expression in inhibitory (VGAT+), serotonergic (tryptophan hydroxylase 2+), and μ-opioid receptor expressing (MOR+) cells. In conclusion, testosterone protects males from development of widespread hyperalgesia through aromatization to estradiol and activation of ER-α which is widely expressed in multiple cell types in the RVM.
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Affiliation(s)
- Ashley N Plumb
- Departments of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa, 52242
| | - Joseph B Lesnak
- Departments of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa, 52242
| | - Louis J Kolling
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa, 52242
| | | | - Kathleen A Sluka
- Departments of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa, 52242
- Neuroscience and Pharmacology, University of Iowa, Iowa City, Iowa, 52242
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2
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Bautista-Abad Á, García-Magro N, Pinto-Benito D, Cáceres-Pajuelo JE, Alises CV, Ganchala D, Lagunas N, Negredo P, García-Segura LM, Arevalo MA, Grassi D. Aging is associated with sex-specific alteration in the expression of genes encoding for neuroestradiol synthesis and signaling proteins in the mouse trigeminal somatosensory input. GeroScience 2024:10.1007/s11357-024-01268-z. [PMID: 38954130 DOI: 10.1007/s11357-024-01268-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 06/25/2024] [Indexed: 07/04/2024] Open
Abstract
Pain perception is influenced by sex and aging, with previous studies indicating the involvement of aromatase, the estradiol synthase enzyme, in regulating pain perception. Previous research has established the presence of aromatase in dorsal root ganglia sensory neurons and its role in modulating pain perception. The present study aims to explore the implications of aging and sex on the expression of aromatase and estrogen receptors in the trigeminal ganglion. The study examined mRNA levels of aromatase, ERs, and the androgen receptor (AR) in the trigeminal ganglion of 3-month-old and 27-month-old male and female mice, as well as 3-month-old mice from the four-core genotype (FCG) transgenic model. The latter facilitates the assessment of gonadal hormone and sex chromosome implications for sex-specific traits. Aromatase localization in the ganglion was further assessed through immunohistochemistry. Aromatase immunoreactivity was observed for the first time in sensory neurons within the trigeminal ganglion. Trigeminal ganglion gene expressions were detected for aromatase, ERs, and AR in both sexes. Aromatase, ERβ, and GPER gene expressions were higher in young males versus young females. Analyses of the FCG model indicated that sex differences depended solely on gonadal sex. The aging process induced an enhancement in the expression of aromatase, ERs, and AR genes across both sexes, culminating in a reversal of the previously observed gender-based differences. the potential impact of estrogen synthesis and signaling in the trigeminal ganglion on age and sex differences warrants consideration, particularly in relation to trigeminal sensory functions and pain perception.
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Affiliation(s)
- Álvaro Bautista-Abad
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain
| | - Nuria García-Magro
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain
- Facultad de Ciencias de la Salud, Universidad Francisco de Vitoria, Ctra. Pozuelo-Majadahonda Km 1,800, Pozuelo de Alarcón, Madrid, Spain
| | - Daniel Pinto-Benito
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Julio Eduardo Cáceres-Pajuelo
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain
| | - Carlos Vicente Alises
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain
| | - Danny Ganchala
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Natalia Lagunas
- Department of Legal Medicine, Psychiatry and Pathology, School of Medicine, Complutense University of Madrid, Plaza Ramón y Cajal s/n, Madrid, Spain
| | - Pilar Negredo
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain
| | - Luis Miguel García-Segura
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid, Spain
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Maria-Angeles Arevalo
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid, Spain.
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain.
| | - Daniela Grassi
- Department of Anatomy, Histology and Neuroscience, Autonoma University of Madrid, Calle Arzobispo Morcillo 4, Madrid, Spain.
- Neuroactive Steroids Lab, Cajal Institute, CSIC, Avenida Doctor Arce 37, Madrid, Spain.
- Centro de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain.
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3
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Vacca V, Rossi C, Pieroni L, De Angelis F, Giacovazzo G, Cicalini I, Ciavardelli D, Pavone F, Coccurello R, Marinelli S. Sex-specific adipose tissue's dynamic role in metabolic and inflammatory response following peripheral nerve injury. iScience 2023; 26:107914. [PMID: 37817933 PMCID: PMC10561049 DOI: 10.1016/j.isci.2023.107914] [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: 05/02/2023] [Revised: 08/30/2023] [Accepted: 09/12/2023] [Indexed: 10/12/2023] Open
Abstract
Epidemiological data and research highlight increased neuropathy and chronic pain prevalence among females, spanning metabolic and normometabolic contexts, including murine models. Prior findings demonstrated diverse immune and neuroimmune responses between genders in neuropathic pain (NeP), alongside distinct protein expression in sciatic nerves. This study unveils adipose tissue's (AT) role in sex-specific NeP responses after peripheral nerve injury. Metabolic assessments, metabolomics, energy expenditure evaluations, AT proteomic analyses, and adipokine mobilization depict distinct AT reactions to nerve damage. Females exhibit altered lipolysis, fatty acid oxidation, heightened energy expenditure, and augmented steroids secretion affecting glucose and insulin metabolism. Conversely, male neuropathy prompts glycolysis, reduced energy expenditure, and lowered unsaturated fatty acid levels. Males' AT promotes regenerative molecules, oxidative stress defense, and stimulates peroxisome proliferator-activated receptors (PPAR-γ) and adiponectin. This study underscores AT's pivotal role in regulating gender-specific inflammatory and metabolic responses to nerve injuries, shedding light on female NeP susceptibility determinants.
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Affiliation(s)
- Valentina Vacca
- National Council of Research - Institute of Biochemistry and Cell Biology, Monterotondo (RM), Italy
| | - Claudia Rossi
- Department of Innovative Technologies in Medicine and Dentistry, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
- Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Luisa Pieroni
- Departmental Faculty of Medicine, UniCamillus - Saint Camillus International University of Health Sciences, 00131 Rome, Italy
- European Center for Brain Research/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
| | - Federica De Angelis
- National Council of Research - Institute of Biochemistry and Cell Biology, Monterotondo (RM), Italy
- European Center for Brain Research/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
| | - Giacomo Giacovazzo
- European Center for Brain Research/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
- Università degli studi di Teramo (UniTE) - Facoltà di Medicina Veterinaria, 64100 Teramo, Italy
| | - Ilaria Cicalini
- Department of Innovative Technologies in Medicine and Dentistry, "G. d'Annunzio" University of Chieti-Pescara, Chieti, Italy
- Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy
| | - Domenico Ciavardelli
- Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy
- School of Medicine, University Kore of Enna, Enna, Italy
| | - Flaminia Pavone
- National Council of Research - Institute of Biochemistry and Cell Biology, Monterotondo (RM), Italy
| | - Roberto Coccurello
- European Center for Brain Research/Santa Lucia Foundation IRCCS, 00143 Rome, Italy
- Institute for Complex Systems (ISC), National Council of Research (CNR), 00185 Rome, Italy
| | - Sara Marinelli
- National Council of Research - Institute of Biochemistry and Cell Biology, Monterotondo (RM), Italy
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de Bournonville C, Lemoine P, Foidart JM, Arnal JF, Lenfant F, Cornil CA. Role of membrane estrogen receptor alpha (ERα) in the rapid regulation of male sexual behavior. J Neuroendocrinol 2023; 35:e13341. [PMID: 37806316 DOI: 10.1111/jne.13341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 08/04/2023] [Accepted: 08/04/2023] [Indexed: 10/10/2023]
Abstract
The activation of male sexual behavior depends on brain estrogen synthesis. Estrogens act through nuclear and membrane receptors producing effects within hours/days or seconds/minutes, respectively. In mice, estrogen receptor alpha (ERα) is the main estrogen receptor (ER) controlling the activation of male sexual behavior. Although neuroestrogens rapidly modulate mouse sexual behavior, it is not known whether these effects involve membrane ERα (mERα). This study combines two complementary approaches to address this question. C451A-ERα mice carry an ERα that cannot signal at the membrane, while estetrol (E4) is a natural estrogen acting as an agonist on nuclear ERα but as an antagonist on membrane ERα. In wild-type males, E4 decreased the number of mounts and intromissions after 10 min. In C451A-ERα males, E4 also altered sexual performance but after 30 min. E4 did not affect time spent near the female in both wild-type and C451A-ERα mice. However, regardless of genotype, the aromatase inhibitor 1,4,6-Androstatriene-3,17-dione (ATD) decreased both sexual performance and the time spent near the female after 10 and 30 min, confirming the key role of aromatization in the rapid control of sexual behavior and motivation. In conclusion, the shift in timing at which the effect of E4 is observed in mice lacking mERα suggests a role for mERα in the regulation of rapid effects of neuroestrogens on sexual performance, thus providing the first demonstration that E4 acts as an antagonist of a mER in the brain. The persisting effect of ATD on behavior in C451A-ERα mice also suggests the implication of another ER.
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Affiliation(s)
| | - Philippine Lemoine
- Laboratory of Neuroendocrinology, GIGA Neurosciences, University of Liège, Liège, Belgium
| | - Jean-Michel Foidart
- Department of Obstetrics and Gynecology, University of Liège, Liège, Belgium
- Estetra SRL, an affiliate company of Mithra Pharmaceuticals, Liège, Belgium
| | - Jean-François Arnal
- Institute of Metabolic and Cardiovascular Diseases (I2MC) Equipe 4, Inserm U1297-UPS, CHU, Toulouse, France
| | - Françoise Lenfant
- Institute of Metabolic and Cardiovascular Diseases (I2MC) Equipe 4, Inserm U1297-UPS, CHU, Toulouse, France
| | - Charlotte A Cornil
- Laboratory of Neuroendocrinology, GIGA Neurosciences, University of Liège, Liège, Belgium
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5
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Kinkead R, Ambrozio-Marques D, Fournier S, Gagnon M, Guay LM. Estrogens, age, and, neonatal stress: panic disorders and novel views on the contribution of non-medullary structures to respiratory control and CO 2 responses. Front Physiol 2023; 14:1183933. [PMID: 37265841 PMCID: PMC10229816 DOI: 10.3389/fphys.2023.1183933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 04/21/2023] [Indexed: 06/03/2023] Open
Abstract
CO2 is a fundamental component of living matter. This chemical signal requires close monitoring to ensure proper match between metabolic production and elimination by lung ventilation. Besides ventilatory adjustments, CO2 can also trigger innate behavioral and physiological responses associated with fear and escape but the changes in brain CO2/pH required to induce ventilatory adjustments are generally lower than those evoking fear and escape. However, for patients suffering from panic disorder (PD), the thresholds for CO2-evoked hyperventilation, fear and escape are reduced and the magnitude of those reactions are excessive. To explain these clinical observations, Klein proposed the false suffocation alarm hypothesis which states that many spontaneous panics occur when the brain's suffocation monitor erroneously signals a lack of useful air, thereby maladaptively triggering an evolved suffocation alarm system. After 30 years of basic and clinical research, it is now well established that anomalies in respiratory control (including the CO2 sensing system) are key to PD. Here, we explore how a stress-related affective disorder such as PD can disrupt respiratory control. We discuss rodent models of PD as the concepts emerging from this research has influenced our comprehension of the CO2 chemosensitivity network, especially structure that are not located in the medulla, and how factors such as stress and biological sex modulate its functionality. Thus, elucidating why hormonal fluctuations can lead to excessive responsiveness to CO2 offers a unique opportunity to gain insights into the neuroendocrine mechanisms regulating this key aspect of respiratory control and the pathophysiology of respiratory manifestations of PD.
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6
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Saldanha CJ. Spatial and temporal specificity of neuroestradiol provision in the songbird. J Neuroendocrinol 2023; 35:e13192. [PMID: 35983989 PMCID: PMC9889572 DOI: 10.1111/jne.13192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/25/2022] [Accepted: 07/26/2022] [Indexed: 02/03/2023]
Abstract
Steroid hormones are often synthesized in multiple tissues, affect several different targets, and modulate numerous physiological endpoints. The mechanisms by which this modulation is achieved with temporal and spatial specificity remain unclear. 17β-estradiol for example, is made in several peripheral tissues and in the brain, where it affects a diverse set of behaviors. How is estradiol delivered to the right target, at the right time, and at the right concentration? In the last two decades, we have learned that aromatase (estrogen-synthase) can be induced in astrocytes following damage to the brain and is expressed at central synapses. Both mechanisms of estrogen provision confer spatial and temporal specificity on a lipophilic neurohormone with potential access to all cells and tissues. In this review, I trace the progress in our understanding of astrocytic and synaptic aromatization. I discuss the incidence, regulation, and functions of neuroestradiol provision by aromatization, first in astrocytes and then at synapses. Finally, I focus on a relatively novel hypothesis about the role of neuroestradiol in the orchestration of species-specific behaviors.
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Affiliation(s)
- Colin J Saldanha
- Departments of Neuroscience and Psychology, and Center for Behavioral Neuroscience, American University, Washington, DC, USA
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7
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Hanna Mossad Samaan M, Mohamed Ahmed Sarhan T, Abd El Azim Ammar R, Hanafy Mahmoud T, Mohamed Ahmed El Shafie A. A study of menstrual cycle effects on pain perception, haemodynamic response to laryngoscopy, and postoperative outcome in gynaecological laparoscopy. EGYPTIAN JOURNAL OF ANAESTHESIA 2022. [DOI: 10.1080/11101849.2022.2147472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Mariam Hanna Mossad Samaan
- Assistant Lecturer in Anaesthesia and Surgical Intensive Care, Alexandria Faculty of Medicine, Alexandria, Egypt
| | - Tarek Mohamed Ahmed Sarhan
- Assistant Lecturer in Anaesthesia and Surgical Intensive Care, Alexandria Faculty of Medicine, Alexandria, Egypt
| | - Ramadan Abd El Azim Ammar
- Assistant Lecturer in Anaesthesia and Surgical Intensive Care, Alexandria Faculty of Medicine, Alexandria, Egypt
| | - Tamer Hanafy Mahmoud
- Professor of Obstetrics and Gynaecology, Alexandria Faculty of Medicine, Alexandria, Egypt
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8
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Chernov AV, Shubayev VI. Sexual dimorphism of early transcriptional reprogramming in degenerating peripheral nerves. Front Mol Neurosci 2022; 15:1029278. [DOI: 10.3389/fnmol.2022.1029278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 10/06/2022] [Indexed: 11/13/2022] Open
Abstract
Sexual dimorphism is a powerful yet understudied factor that influences the timing and efficiency of gene regulation in axonal injury and repair processes in the peripheral nervous system. Here, we identified common and distinct biological processes in female and male degenerating (distal) nerve stumps based on a snapshot of transcriptional reprogramming 24 h after axotomy reflecting the onset of early phase Wallerian degeneration (WD). Females exhibited transcriptional downregulation of a larger number of genes than males. RhoGDI, ERBB, and ERK5 signaling pathways increased activity in both sexes. Males upregulated genes and canonical pathways that exhibited robust baseline expression in females in both axotomized and sham nerves, including signaling pathways controlled by neuregulin and nerve growth factors. Cholesterol biosynthesis, reelin signaling, and synaptogenesis signaling pathways were downregulated in females. Signaling by Rho Family GTPases, cAMP-mediated signaling, and sulfated glycosaminoglycan biosynthesis were downregulated in both sexes. Estrogens potentially influenced sex-dependent injury response due to distinct regulation of estrogen receptor expression. A crosstalk of cytokines and growth hormones could promote sexually dimorphic transcriptional responses. We highlighted prospective regulatory activities due to protein phosphorylation, extracellular proteolysis, sex chromosome-specific expression, major urinary proteins (MUPs), and genes involved in thyroid hormone metabolism. Combined with our earlier findings in the corresponding dorsal root ganglia (DRG) and regenerating (proximal) nerve stumps, sex-specific and universal early phase molecular triggers of WD enrich our knowledge of transcriptional regulation in peripheral nerve injury and repair.
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Xie Z, Feng J, Cai T, McCarthy R, Eschbach Ii MD, Wang Y, Zhao Y, Yi Z, Zang K, Yuan Y, Hu X, Li F, Liu Q, Das A, England SK, Hu H. Estrogen metabolites increase nociceptor hyperactivity in a mouse model of uterine pain. JCI Insight 2022; 7:149107. [PMID: 35420999 PMCID: PMC9220826 DOI: 10.1172/jci.insight.149107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/12/2022] [Indexed: 11/17/2022] Open
Abstract
Pain emanating from the female reproductive tract is notoriously difficult to be treated and the prevalence of transient pelvic pain has been placed as high as 70-80% in women surveyed. Although sex hormones, especially estrogen, are thought to underlie enhanced pain perception in females, the underlying molecular and cellular mechanisms are not completely understood. Here we show that the pain-initiating TRPA1 channel is required for pain-related behaviors in a mouse model of estrogen-induced uterine pain in ovariectomized female mice. Surprisingly, 2- and 4-hydroxylated estrogen metabolites (HEMs) in the estrogen hydroxylation pathway, but not estrone, estradiol and 16-HEMs, directly increase nociceptor hyperactivity through TRPA1 and TRPV1 channels, and picomolar concentrations of 2- and 4-hydroxylation estrone (OHE1) can sensitize TRPA1 channel function. Moreover, both TRPA1 and TRPV1 are expressed in uterine-innervating primary nociceptors and their expressions are increased in the estrogen-induced uterine pain model. Importantly, pretreatment of 2- or 4-OHE1 recapitulates estrogen-induced uterine pain-like behaviors and intraplantar injections of 2- and 4-OHE1 directly produce a TRPA1-dependent mechanical hypersensitivity. Our findings demonstrate that TRPA1 is critically involved in estrogen-induced uterine pain-like behaviors, which may provide a potential drug target for treating female reproductive tract pain.
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Affiliation(s)
- Zili Xie
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Jing Feng
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Tao Cai
- The First Affiliated Hospital of Chongqing Medical University, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ronald McCarthy
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, United States of America
| | - Mark D Eschbach Ii
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, United States of America
| | - Yuhui Wang
- Department of Anesthesiology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yonghui Zhao
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Zhihua Yi
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Kaikai Zang
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Yi Yuan
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Xueming Hu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Fengxian Li
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Qin Liu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Aditi Das
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, United States of America
| | - Sarah K England
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, United States of America
| | - Hongzhen Hu
- Washington University School of Medicine, St. Louis, United States of America
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10
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Chow LH, Wu WC, Kuo CL, Hung HY, Chen YH, Pan W, Huang EYK. Estrogen can abolish oxytocin-induced spinal anti-hyperalgesia. Psychoneuroendocrinology 2022; 136:105603. [PMID: 34891047 DOI: 10.1016/j.psyneuen.2021.105603] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 11/19/2021] [Accepted: 11/19/2021] [Indexed: 11/28/2022]
Abstract
Our previous study verified a sex difference of anti-hyperalgesia in rats and anti-allodynia in mice induced by intrathecal oxytocin (OT). In the model of intraplantar carrageenan-induced inflammatory hyperalgesia, intrathecal OT injection induced a substantial anti-hyperalgesia in male rats even at a low dose (0.125 nmol). In contrast, female rats only responded to an extremely high dose (1.25 nmol). This sex difference concurs with a lower expression of OT receptors and higher expression of insulin-regulated aminopeptidase (IRAP; OT degrading enzyme) in the spinal cords of female rats. In this study, we further determined the role of female hormones in this sex difference by using ovariectomized rats. Our results show that a low dose of intrathecal OT caused a significant anti-hyperalgesia effect in ovariectomized female rats, similar to that seen in male rats. Ovariectomy did not cause any change of paw edema except at the late stage of convalescence when compared with the sham-operated group. Ovariectomy-induced faster recovery from edema but did not affect the severity of hyperalgesia. Moreover, there was a similar amount of IRAP expression in ovariectomized and sham rats. When estradiol (E2) was given together with OT, OT-induced anti-hyperalgesia was abolished at the developmental stage of hyperalgesia in ovariectomized rats. These results show an inhibitory role of female hormones generated from ovaries (mainly estrogen) in the sex difference of anti-hyperalgesia induced by OT. This study suggests the feasibility of a novel OT-based remedy to treat hyperalgesia in men and in menopausal women no receiving hormonal supplements.
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Affiliation(s)
- Lok-Hi Chow
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; Department of Anesthesiology, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Anesthesiology, School of Medicine, National Yang-Ming Chiao-Tung University, Taipei, Taiwan; Department of Anesthesiology, National Defense Medical Center, Taipei, Taiwan
| | - Wan-Chuan Wu
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Chun-Lin Kuo
- Department of General Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Hao-Yuan Hung
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan; Department of Pharmacy Practice, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Yuan-Hao Chen
- Department of Neurological Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Weihong Pan
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; BioPotentials Consult, Sedona, AZ, United States
| | - Eagle Yi-Kung Huang
- Department of Pharmacology, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan.
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11
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Chernov AV, Shubayev VI. Sexual Dimorphism of Early Transcriptional Reprogramming in Dorsal Root Ganglia After Peripheral Nerve Injury. Front Mol Neurosci 2021; 14:779024. [PMID: 34966260 PMCID: PMC8710713 DOI: 10.3389/fnmol.2021.779024] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 11/19/2021] [Indexed: 01/18/2023] Open
Abstract
Peripheral nerve injury induces genome-wide transcriptional reprogramming of first-order neurons and auxiliary cells of dorsal root ganglia (DRG). Accumulating experimental evidence suggests that onset and mechanistic principles of post-nerve injury processes are sexually dimorphic. We examined largely understudied aspects of early transcriptional events in DRG within 24 h after sciatic nerve axotomy in mice of both sexes. Using high-depth RNA sequencing (>50 million reads/sample) to pinpoint sexually dimorphic changes related to regeneration, immune response, bioenergy, and sensory functions, we identified a higher number of transcriptional changes in male relative to female DRG. In males, the decline in ion channel transcripts was accompanied by the induction of innate immune cascades via TLR, chemokine, and Csf1-receptor axis and robust regenerative programs driven by Sox, Twist1/2, and Pax5/9 transcription factors. Females demonstrated nerve injury-specific transcriptional co-activation of the actinin 2 network. The predicted upstream regulators and interactive networks highlighted the role of novel epigenetic factors and genetic linkage to sex chromosomes as hallmarks of gene regulation post-axotomy. We implicated epigenetic X chromosome inactivation in the regulation of immune response activity uniquely in females. Sexually dimorphic regulation of MMP/ADAMTS metalloproteinases and their intrinsic X-linked regulator Timp1 contributes to extracellular matrix remodeling integrated with pro-regenerative and immune functions. Lexis1 non-coding RNA involved in LXR-mediated lipid metabolism was identified as a novel nerve injury marker. Together, our data identified unique early response triggers of sex-specific peripheral nerve injury regulation to gain mechanistic insights into the origin of female- and male-prevalent sensory neuropathies.
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Affiliation(s)
- Andrei V Chernov
- Department of Anesthesiology, University of California, San Diego, San Diego, CA, United States.,VA San Diego Healthcare System, San Diego, CA, United States
| | - Veronica I Shubayev
- Department of Anesthesiology, University of California, San Diego, San Diego, CA, United States.,VA San Diego Healthcare System, San Diego, CA, United States
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12
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Arbiters of endogenous opioid analgesia: role of CNS estrogenic and glutamatergic systems. Transl Res 2021; 234:31-42. [PMID: 33567346 PMCID: PMC8217383 DOI: 10.1016/j.trsl.2021.02.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 11/24/2022]
Abstract
Nociception and opioid antinociception in females are pliable processes, varying qualitatively and quantitatively over the reproductive cycle. Spinal estrogenic signaling via membrane estrogen receptors (mERs), in combination with multiple other signaling molecules [spinal dynorphin, kappa-opioid receptors (KOR), glutamate and metabotropic glutamate receptor 1 (mGluR1)], appears to function as a master coordinator, parsing functionality between pronociception and antinociception. This provides a window into pharmacologically accessing intrinsic opioid analgesic/anti-allodynic systems. In diestrus, membrane estrogen receptor alpha (mERα) signals via mGluR1 to suppress spinal endomorphin 2 (EM2) analgesia. Strikingly, in the absence of exogenous opioids, interfering with this suppression in a chronic pain model elicits opioid anti-allodynia, revealing contributions of endogenous opioid(s). In proestrus, robust spinal EM2 analgesia is manifest but this requires spinal dynorphin/KOR and glutamate-activated mGluR1. Furthermore, spinal mGluR1 blockade in a proestrus chronic pain animal (eliminating spinal EM2 analgesia) exacerbates mechanical allodynia, revealing tempering by endogenous opioid(s). A complex containing mu-opioid receptor, KOR, aromatase, mGluRs, and mERα are foundational to eliciting endogenous opioid anti-allodynia. Aromatase-mERα oligomers are also plentiful, in a central nervous system region-specific fashion. These can be independently regulated and allow estrogens to act intracellularly within the same signaling complex in which they are synthesized, explaining asynchronous relationships between circulating estrogens and central nervous system estrogen functionalities. Observations with EM2 highlight the translational relevance of extensively characterizing exogenous responsiveness to endogenous opioids and the neuronal circuits that mediate them along with the multiplicity of estrogenic systems that concomitantly function in phase and out-of-phase with the reproductive cycle.
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13
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Collin A, Vein J, Wittrant Y, Pereira B, Amode R, Guillet C, Richard D, Eschalier A, Balayssac D. A new clinically-relevant rat model of letrozole-induced chronic nociceptive disorders. Toxicol Appl Pharmacol 2021; 425:115600. [PMID: 34081940 DOI: 10.1016/j.taap.2021.115600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 05/15/2021] [Accepted: 05/28/2021] [Indexed: 12/21/2022]
Abstract
Among postmenopausal women with estrogen receptor-positive breast cancer, more than 80% receive hormone therapy including aromatase inhibitors (AIs). Half of them develop chronic arthralgia - characterized by symmetric articular pain, carpal tunnel syndrome, morning stiffness, myalgia and a decrease in grip strength - which is associated with treatment discontinuation. Only a few animal studies have linked AI treatment to nociception, and none to arthralgia. Thus, we developed a new chronic AI-induced nociceptive disorder model mimicking clinical symptoms induced by AIs, using subcutaneous letrozole pellets in ovariectomized (OVX) rats. Following plasma letrozole dosage at the end of the experiment (day 73), only rats with at least 90 ng/ml of letrozole were considered significantly exposed to letrozole (OVX + high LTZ group), whereas treated animals with less than 90 ng/ml were pooled in the OVX + low LTZ group. Chronic nociceptive disorder set in rapidly and was maintained for more than 70 days in the OVX + high LTZ group. Furthermore, OVX + high LTZ rats saw no alteration in locomotion, myalgia or experimental anxiety during this period. Bone parameters of the femora were significantly altered in all OVX rats compared to Sham+vehicle pellet. A mechanistic analysis focused on TRPA1, receptor suspected to mediate AI-evoked pain, and showed no modification in its expression in the DRG. This new long-lasting chronic rat model, efficiently reproduces the symptoms of AI-induced nociceptive disorder affecting patients' daily activities and quality-of-life. It should help to study the pathophysiology of this disorder and to promote the development of new therapeutic strategies.
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Affiliation(s)
- Aurore Collin
- Université Clermont Auvergne, INSERM, U1107, NEURO-DOL, F-63000 Clermont-Ferrand, France.
| | - Julie Vein
- Université Clermont Auvergne, INSERM, U1107, NEURO-DOL, F-63000 Clermont-Ferrand, France
| | - Yohann Wittrant
- Université Clermont Auvergne, INRA, UNH, 63000 Clermont-Ferrand, France; INRAE, UMR 1019, UNH, 63122 Saint-Genès Champanelle, France
| | - Bruno Pereira
- CHU Clermont-Ferrand, Direction de la recherche clinique et de l'innovation, F-63000 Clermont-Ferrand, France
| | - Raalib Amode
- School of Pharmacy, Faculty of Science, University of East Anglia, UK
| | - Christelle Guillet
- Université Clermont Auvergne, INRA, UMR1019, UNH, CRNH Auvergne, F-63000 Clermont-Ferrand, France
| | - Damien Richard
- Université Clermont Auvergne, INSERM U1107, NEURO-DOL, CHU Clermont-Ferrand, Laboratoire de Pharmacologie et de Toxicologie, F-63000 Clermont-Ferrand, France
| | - Alain Eschalier
- Université Clermont Auvergne, INSERM, U1107, NEURO-DOL, F-63000 Clermont-Ferrand, France
| | - David Balayssac
- Université Clermont Auvergne, INSERM U1107, NEURO-DOL, CHU Clermont-Ferrand, Direction de la recherche clinique et de l'innovation, F-63000 Clermont-Ferrand, France.
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14
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Tran M, Braz JM, Hamel K, Kuhn J, Todd AJ, Basbaum AI. Ablation of spinal cord estrogen receptor α-expressing interneurons reduces chemically induced modalities of pain and itch. J Comp Neurol 2020; 528:1629-1643. [PMID: 31872868 PMCID: PMC7317200 DOI: 10.1002/cne.24847] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/13/2019] [Accepted: 12/16/2019] [Indexed: 11/13/2022]
Abstract
Estrogens are presumed to underlie, at least in part, the greater pain sensitivity and chronic pain prevalence that women experience compared to men. Although previous studies revealed populations of estrogen receptor-expressing neurons in primary afferents and in superficial dorsal horn neurons, there is little to no information as to the contribution of these neurons to the generation of acute and chronic pain. Here we molecularly characterized neurons in the mouse superficial spinal cord dorsal horn that express estrogen receptor α (ERα) and explored the behavioral consequences of their ablation. We found that spinal ERα-positive neurons are largely excitatory interneurons and many coexpress substance P, a marker for a discrete subset of nociceptive, excitatory interneurons. After viral, caspase-mediated ablation of spinal ERα-expressing cells, we observed a significant decrease in the first phase of the formalin test, but in male mice only. ERα-expressing neuron-ablation also reduced pruritogen-induced scratching in both male and female mice. There were no ablation-related changes in mechanical or heat withdrawal thresholds or in capsaicin-induced nocifensive behavior. In chronic pain models, we found no change in Complete Freund's adjuvant-induced thermal or mechanical hypersensitivity, or in partial sciatic nerve injury-induced mechanical allodynia. We conclude that ERα labels a subpopulation of excitatory interneurons that are specifically involved in chemically evoked persistent pain and pruritogen-induced itch.
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Affiliation(s)
- May Tran
- Department of AnatomyUniversity of CaliforniaSan FranciscoCalifornia
| | - Joao Manuel Braz
- Department of AnatomyUniversity of CaliforniaSan FranciscoCalifornia
| | - Katherine Hamel
- Department of AnatomyUniversity of CaliforniaSan FranciscoCalifornia
| | - Julia Kuhn
- Department of AnatomyUniversity of CaliforniaSan FranciscoCalifornia
| | - Andrew J. Todd
- Spinal Cord Group, Institute of Neuroscience and Psychology, College of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Allan I. Basbaum
- Department of AnatomyUniversity of CaliforniaSan FranciscoCalifornia
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15
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Jiang M, Liu Y, Wu H, Ma Z, Gu X. High Estrogen Level Modifies Postoperative Hyperalgesia via GPR30 and MMP-9 in Dorsal Root Ganglia Neurons. Neurochem Res 2020; 45:1661-1673. [PMID: 32303987 DOI: 10.1007/s11064-020-03032-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 03/17/2020] [Accepted: 04/10/2020] [Indexed: 12/18/2022]
Abstract
The cycling of sex hormones is one of the factors affecting pain in females, and the mechanisms are not fully understood. G-protein coupled estrogen receptor 30 (GPR30) is the estrogen receptor known to be involved in mechanical hyperalgesia. Studies have demonstrated that matrix metalloproteinase-9 (MMP-9) is a critical component in peripheral/central nervous system hypersensitivity and neuroinflammation, both of which participate in hyperalgesia. Here, ovariectomized rats were treated with low or high dose estrogen replacement, and then plantar incisions were made. Subsequently, mechanical allodynia was evaluated by determining the paw withdrawal mechanical threshold before and after the incision. In rats with incisions, high estrogen levels induced postoperative hyperalgesia and upregulation of GPR30 and MMP-9 in dorsal root ganglia (DRGs). MMP-9 was expressed primarily in DRG neurons co-expressing GPR30, and led to the activation of IL-1β. After intrathecal injection of the GPR30 agonist G1, female rats with low estrogen and plantar incisions continued to exhibit significant hyperalgesia until 48 h post-incision. In high estrogen level rats with plantar incisions, intrathecal injection of GPR30 antagonist G15 significantly attenuated postoperative hyperalgesia. Intraperitoneal injection of N-acetyl-cysteine, a source of cysteine that prevents the oxidation of cysteine residues on MMP-9, significantly relieved high estrogen-induced postoperative hyperalgesia via suppression of MMP-9 and IL-1β activation in DRGs. These results demonstrate that high estrogen level in rats with incisions elicit GPR30 and MMP-9 upregulation in DRGs and subsequently activate IL-1β, leading to induced postoperative hyperalgesia.
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Affiliation(s)
- Ming Jiang
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Yue Liu
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Hao Wu
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Zhengliang Ma
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China
| | - Xiaoping Gu
- Department of Anesthesiology, Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, 210008, Jiangsu, China.
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16
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Balthazart J. New concepts in the study of the sexual differentiation and activation of reproductive behavior, a personal view. Front Neuroendocrinol 2019; 55:100785. [PMID: 31430485 PMCID: PMC6858558 DOI: 10.1016/j.yfrne.2019.100785] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 08/13/2019] [Accepted: 08/16/2019] [Indexed: 01/09/2023]
Abstract
Since the beginning of this century, research methods in neuroendocrinology enjoyed extensive refinements and innovation. These advances allowed collection of huge amounts of new data and the development of new ideas but have not led to this point, with a few exceptions, to the development of new conceptual advances. Conceptual advances that took place largely resulted from the ingenious insights of several investigators. I summarize here some of these new ideas as they relate to the sexual differentiation and activation by sex steroids of reproductive behaviors and I discuss how our research contributed to the general picture. This selective review clearly demonstrates the importance of conceptual changes that have taken place in this field since beginning of the 21st century. The recent technological advances suggest that our understanding of hormones, brain and behavior relationships will continue to improve in a very fundamental manner over the coming years.
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17
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Gintzler AR, Storman EM, Liu NJ. Estrogens as arbiters of sex-specific and reproductive cycle-dependent opioid analgesic mechanisms. VITAMINS AND HORMONES 2019; 111:227-246. [PMID: 31421702 PMCID: PMC7136895 DOI: 10.1016/bs.vh.2019.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The organization of estrogenic signaling in the CNS is exceedingly complex. It is comprised of peripherally and centrally synthesized estrogens, and a plethora of types of estrogen receptor that can localize to both the nucleus and the plasma membrane. Moreover, CNS estrogen receptors can exist independent of aromatase (aka estrogen synthase) as well as oligomerize with it, along with a host of other membrane signaling proteins. This ability of CNS estrogen receptors to either to physically pair or exist separately enables locally produced estrogens to act on multiple spatial levels, with a high degree of gradated regulation and plasticity, signaling either in-phase or out-of phase with circulating estrogens. This complexity explains the numerous contradictory findings regarding sex-dependent pain processing and sexually dimorphic opioid antinociception. This review highlights the increasing awareness that estrogens are major endogenous arbiters of both opioid analgesic actions and the mechanisms used to achieve them. This behooves us to understand, and possibly intercede at, the points of intersection of estrogenic signaling and opioid functionality. Factors that integrate estrogenic actions at subcellular, synaptic, and CNS regional levels are likely to be prime drug targets for novel pharmacotherapies designed to modulate CNS estrogen-dependent opioid functionalities and possibly circumvent the current opioid epidemic.
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MESH Headings
- Analgesia
- Analgesics, Opioid/pharmacology
- Animals
- Aromatase
- Brain/physiology
- Dynorphins/physiology
- Estrogens/physiology
- Female
- Humans
- Male
- Neurosecretory Systems/physiology
- Nociception/drug effects
- Nociception/physiology
- Receptors, Estrogen/physiology
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/physiology
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/physiology
- Reproduction/physiology
- Sex Characteristics
- Signal Transduction/physiology
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Affiliation(s)
- Alan R Gintzler
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, NY, United States.
| | - Emiliya M Storman
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, NY, United States
| | - Nai-Jiang Liu
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, NY, United States
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18
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Progesterone relates to enhanced incisional acute pain and pinprick hyperalgesia in the luteal phase of female volunteers. Pain 2019; 160:1781-1793. [DOI: 10.1097/j.pain.0000000000001561] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Bereiter DA, Thompson R, Rahman M. Sex Differences in Estradiol Secretion by Trigeminal Brainstem Neurons. Front Integr Neurosci 2019; 13:3. [PMID: 30809134 PMCID: PMC6379465 DOI: 10.3389/fnint.2019.00003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 01/22/2019] [Indexed: 12/01/2022] Open
Abstract
Estrogen status is a significant risk factor in the development of temporomandibular joint disorders (TMD). Classically, estrogen status is thought to derive mainly from ovarian sources; however, it is well known that estradiol (E2) also is synthesized by neurons in the brain. This study tested the hypothesis that E2 is produced by neurons in trigeminal subnucleus caudalis (Vc), the principal site of termination for sensory afferents that supply the temporomandibular joint (TMJ), to modify evoked responses in a model of TMJ nociception in male and female rats. Intra-TMJ injection of the small fiber excitant, allyl isothiocyanate (AIC), increased the levels of E2 collected from microdialysis probes sites at Vc of ovariectomized (OvX) female rats, ipsilateral to the stimulus, whereas males displayed no change. Dialysate levels of E2 collected from probe sites in the contralateral Vc or cerebellum in OvX rats were not affected by TMJ stimulation. Reverse dialysis of anastrozole, an aromatase (ARO) inhibitor, via the probe reduced perfusate levels of E2 in Vc. Systemic administration of letrozole, a non-steroid ARO inhibitor, for 4 days prevented TMJ-evoked increases in masseter muscle electromyography (MMemg) activity. ARO-positive neurons were distributed mainly in superficial laminae (I-III) at Vc and cell counts revealed no significant difference between OvX and male rats. Intra-TMJ injection of AIC revealed similar numbers of ARO/Fos dual-labeled neurons in OvX and male rats. By contrast, the percentage of ARO neurons co-labeled for glutamic acid decarboxylase (GAD), the biosynthetic enzyme for GABA, was greater in OvX (35%) than male rats (14%). Few ARO-positive neurons were co-labeled for estrogen receptor alpha. These data indicate that E2 is secreted continuously by Vc neurons and that acute stimulation of TMJ nociceptors evokes further secretion in a sex-dependent manner. Reduced TMJ-evoked MMemg activity after ARO inhibition suggests that locally produced E2 by Vc neurons acts via paracrine mechanisms to modify TMJ nociception in female rats.
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Affiliation(s)
- David A Bereiter
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN, United States
| | - Randall Thompson
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN, United States
| | - Mostafeezur Rahman
- Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry, Minneapolis, MN, United States
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20
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Gintzler AR, Liu NJ, Storman EM, Wessendorf MW. Exploiting endogenous opioids: Lessons learned from endomorphin 2 in the female rat. Peptides 2019; 112:133-138. [PMID: 30557590 PMCID: PMC7173356 DOI: 10.1016/j.peptides.2018.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 11/30/2018] [Accepted: 12/03/2018] [Indexed: 02/06/2023]
Abstract
Effective management of chronic pain is demanded by ethical as well as medical considerations. Although opioid analgesics remain among the most effective pharmacotherapies for ameliorating many types of pain, their use is clouded by concerns regarding their addictive properties, underscored by the current epidemic of prescription opioid abuse and attendant deaths. Medicinal harnessing of endogenous opioid antinociception could provide a strategy for continuing to take advantage of the powerful antinociceptive properties of opioids while avoiding their abuse potential. Based on our studies of endogenous mechanism that suppress and facilitate spinal endomorphin 2 antinociception over the rat reproductive cycle, we identified multiple signaling molecules that could serve as targets for activating endogenous opioid analgesia for chronic pain management in women. Our findings emphasize the need for a precision medicine approach that includes stage of menstrual cycle as an important determinant of drug targets for (activating/harnessing) endogenous opioid antinociceptive systems/ capabilities. Utilization of drugs that harness endogenous opioid antinociception in accordance with varying physiological states represents a novel approach for effective pain management.
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Affiliation(s)
- Alan R Gintzler
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA.
| | - Nai-Jiang Liu
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA
| | - Emiliya M Storman
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, 450 Clarkson Ave, Brooklyn, NY, 11203, USA
| | - Martin W Wessendorf
- Department of Neuroscience, School of Medicine, University of Minnesota, Minneapolis, MN 55455, USA
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21
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Khariv V, Acioglu C, Ni L, Ratnayake A, Li L, Tao YX, Heary RF, Elkabes S. A link between plasma membrane calcium ATPase 2 (PMCA2), estrogen and estrogen receptor α signaling in mechanical pain. Sci Rep 2018; 8:17260. [PMID: 30467368 PMCID: PMC6250714 DOI: 10.1038/s41598-018-35263-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/30/2018] [Indexed: 12/29/2022] Open
Abstract
Earlier studies on genetically modified mice indicated that plasma membrane calcium ATPase 2 (PMCA2), a calcium extrusion pump, plays a novel and sex-dependent role in mechanical pain responses: female, but not male, PMCA2+/− mice manifest increased mechanical pain compared to female PMCA2+/+ mice. The goal of the present studies was to determine the contribution of ovarian steroids to the genotype- and sex-dependent manifestation of mechanical pain in PMCA2+/+ versus PMCA2+/− mice. Ovariectomy increased mechanical pain sensitivity and 17β-estradiol (E2) replacement restored it to basal levels in PMCA2+/+ mice, but not in PMCA2+/− littermates. Intrathecal administration of an estrogen receptor alpha (ERα) agonist induced ERα signaling in the dorsal horn (DH) of female PMCA2+/+ mice, but was ineffective in PMCA2+/− mice. In male PMCA2+/+ and PMCA2+/− mice, E2 treatment following orchidectomy did not recapitulate the genotype-dependent differential pain responses observed in females and the agonist did not elicit ERα signaling. These findings establish a novel, female-specific link between PMCA2, ERα and mechanical pain. It is postulated that PMCA2 is essential for adequate ERα signaling in the female DH and that impaired ERα signaling in the female PMCA2+/− mice hinders the analgesic effects of E2 leading to increased sensitivity to mechanical stimuli.
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Affiliation(s)
- Veronika Khariv
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA.,The School of Graduate Studies, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, 07103, USA
| | - Cigdem Acioglu
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA
| | - Li Ni
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA
| | - Ayomi Ratnayake
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA
| | - Lun Li
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA.,The School of Graduate Studies, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, 07103, USA
| | - Yuan-Xiang Tao
- Department of Anesthesiology, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, 07103, USA
| | - Robert F Heary
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA
| | - Stella Elkabes
- Department of Neurological Surgery, The Reynolds Family Spine Laboratory, New Jersey Medical School, Rutgers,The State University of New Jersey, Newark, NJ, 07103, USA.
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22
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Nourbakhsh F, Atabaki R, Roohbakhsh A. The role of orphan G protein-coupled receptors in the modulation of pain: A review. Life Sci 2018; 212:59-69. [PMID: 30236869 DOI: 10.1016/j.lfs.2018.09.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 09/04/2018] [Accepted: 09/14/2018] [Indexed: 12/16/2022]
Abstract
G protein-coupled receptors (GPCRs) comprise a large number of receptors. Orphan GPCRs are divided into six families. These groups contain orphan receptors for which the endogenous ligands are unclear. They have various physiological effects in the body and have the potential to be used in the treatment of different diseases. Considering their important role in the central and peripheral nervous system, their role in the treatment of pain has been the subject of some recent studies. At present, there are effective therapeutics for the treatment of pain including opioid medications and non-steroidal anti-inflammatory drugs. However, the side effects of these drugs and the risks of tolerance and dependence remain a major problem. In addition, neuropathic pain is a condition that does not respond to currently available analgesic medications well. In the present review article, we aimed to review the most recent findings regarding the role of orphan GPCRs in the treatment of pain. Accordingly, based on the preclinical findings, the role of GPR3, GPR7, GPR8, GPR18, GPR30, GPR35, GPR40, GPR55, GPR74, and GPR147 in the treatment of pain was discussed. The present study highlights the role of orphan GPCRs in the modulation of pain and implies that these receptors are potential new targets for finding better and more efficient therapeutics for the management of pain particularly neuropathic pain.
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Affiliation(s)
- Fahimeh Nourbakhsh
- Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Rabi Atabaki
- Rayan Center for Neuroscience & Behavior, Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Ali Roohbakhsh
- Pharmaceutical Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
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Vahaba DM, Remage-Healey L. Neuroestrogens rapidly shape auditory circuits to support communication learning and perception: Evidence from songbirds. Horm Behav 2018; 104:77-87. [PMID: 29555375 PMCID: PMC7025793 DOI: 10.1016/j.yhbeh.2018.03.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 03/15/2018] [Accepted: 03/15/2018] [Indexed: 12/19/2022]
Abstract
Contribution to Special Issue on Fast effects of steroids. Steroid hormones, such as estrogens, were once thought to be exclusively synthesized in the ovaries and enact transcriptional changes over the course of hours to days. However, estrogens are also locally synthesized within neural circuits, wherein they rapidly (within minutes) modulate a range of behaviors, including spatial cognition and communication. Here, we review the role of brain-derived estrogens (neuroestrogens) as modulators within sensory circuits in songbirds. We first present songbirds as an attractive model to explore how neuroestrogens in auditory cortex modulate vocal communication processing and learning. Further, we examine how estrogens may enhance vocal learning and auditory memory consolidation in sensory cortex via mechanisms similar to those found in the hippocampus of rodents and birds. Finally, we propose future directions for investigation, including: 1) the extent of developmental and hemispheric shifts in aromatase and membrane estrogen receptor expression in auditory circuits; 2) how neuroestrogens may impact inhibitory interneurons to regulate audition and critical period plasticity; and, 3) dendritic spine plasticity as a candidate mechanism mediating estrogen-dependent effects on vocal learning. Together, this perspective of estrogens as neuromodulators in the vertebrate brain has opened new avenues in understanding sensory plasticity, including how hormones can act on communication circuits to influence behaviors in other vocal learning species, such as in language acquisition and speech processing in humans.
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Affiliation(s)
- Daniel M Vahaba
- Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts Amherst, Amherst, MA 01003, United States
| | - Luke Remage-Healey
- Neuroscience and Behavior Program, Center for Neuroendocrine Studies, University of Massachusetts Amherst, Amherst, MA 01003, United States.
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Estrogens synthesized and acting within a spinal oligomer suppress spinal endomorphin 2 antinociception: ebb and flow over the rat reproductive cycle. Pain 2018; 158:1903-1914. [PMID: 28902684 DOI: 10.1097/j.pain.0000000000000991] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The magnitude of antinociception elicited by intrathecal endomorphin 2 (EM2), an endogenous mu-opioid receptor (MOR) ligand, varies across the rat estrous cycle. We now report that phasic changes in analgesic responsiveness to spinal EM2 result from plastic interactions within a novel membrane-bound oligomer containing estrogen receptors (mERs), aromatase (aka estrogen synthase), metabotropic glutamate receptor 1 (mGluR1), and MOR. During diestrus, spinal mERs, activated by locally synthesized estrogens, act with mGluR1 to suppress spinal EM2/MOR antinociception. The emergence of robust spinal EM2 antinociception during proestrus results from the loss of mER-mGluR1 suppression, a consequence of altered interactions within the oligomer. The chemical pairing of aromatase with mERs within the oligomer containing MOR and mGluR1 allows estrogens to function as intracellular messengers whose synthesis and actions are confined to the same signaling oligomer. This form of estrogenic signaling, which we term "oligocrine," enables discrete, highly compartmentalized estrogen/mER-mGluR1 signaling to regulate MOR-mediated antinociception induced by EM2. Finally, spinal neurons were observed not only to coexpress MOR, mERα, aromatase, and mGluR1 but also be apposed by EM2 varicosities. This suggests that modulation of spinal analgesic responsiveness to exogenous EM2 likely reflects changes in its endogenous analgesic activity. Analogous suppression of spinal EM2 antinociception in women (eg, around menses, comparable with diestrus in rats) as well as the (pathological) inability to transition out of that suppressed state at other menstrual cycle stages could underlie, at least in part, the much greater prevalence and severity of chronic pain in women than men.
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Choi HS, Lee MJ, Choi SR, Smeester BA, Beitz AJ, Lee JH. Spinal Sigma-1 Receptor-mediated Dephosphorylation of Astrocytic Aromatase Plays a Key Role in Formalin-induced Inflammatory Nociception. Neuroscience 2018; 372:181-191. [PMID: 29289721 DOI: 10.1016/j.neuroscience.2017.12.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 12/19/2017] [Accepted: 12/20/2017] [Indexed: 01/08/2023]
Abstract
Aromatase is a key enzyme responsible for the biosynthesis of estrogen from testosterone. Although recent evidence indicates that spinal cord aromatase participates in nociceptive processing, the mechanisms underlying its regulation and its involvement in nociception remain unclear. The present study focuses on the potential role of astrocyte aromatase in formalin-induced acute pain and begins to uncover one mechanism by which spinal aromatase activation is controlled. Following intraplantar formalin injection, nociceptive responses were quantified and immunohistochemistry/co-immunoprecipitation assays were used to investigate the changes in spinal Fos expression and the phospho-serine levels of spinal aromatase. Intrathecal (i.t.) injection of letrozole (an aromatase inhibitor) mitigated both the late phase formalin-induced nociceptive responses and formalin-induced spinal Fos expression. Furthermore, formalin-injected mice showed significantly reduced phospho-serine levels of aromatase, which is associated with the rapid activation of this enzyme. However, sigma-1 receptor inhibition with i.t. BD1047 blocked the dephosphorylation of aromatase and potentiated the pharmacological effect of letrozole on formalin-induced nociceptive responses. In addition, i.t. administration of a sub-effective dose of BD1047 potentiated the pharmacological effect of cyclosporin A (a calcineurin inhibitor) on both the formalin-induced reduction in phospho-serine levels of aromatase and nociceptive behavior. These results suggest that dephosphorylation is an important regulatory mechanism involved in the rapid activation of aromatase and that spinal sigma-1 receptors mediate this dephosphorylation of aromatase through an intrinsic calcineurin pathway.
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Affiliation(s)
- Hoon-Seong Choi
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Mi-Ji Lee
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Sheu-Ran Choi
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Branden A Smeester
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN, USA
| | - Alvin J Beitz
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul, MN, USA
| | - Jang-Hern Lee
- Department of Veterinary Physiology, BK21 PLUS Program for Creative Veterinary Science Research, Research Institute for Veterinary Science and College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea.
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26
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Hernandez-Leon A, De la Luz-Cuellar YE, Granados-Soto V, González-Trujano ME, Fernández-Guasti A. Sex differences and estradiol involvement in hyperalgesia and allodynia in an experimental model of fibromyalgia. Horm Behav 2018; 97:39-46. [PMID: 29080671 DOI: 10.1016/j.yhbeh.2017.10.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 09/21/2017] [Accepted: 10/24/2017] [Indexed: 01/04/2023]
Abstract
Fibromyalgia (FM) is a musculoskeletal chronic pain syndrome. Its prevalence in women is higher than in men possibly by hormonal factors given that symptoms are aggravated during sex hormone-related events, such as the premenstrual period, pregnancy, postpartum or menopause. The aim of the present study was to investigate whether hyperalgesia and allodynia, in reserpine-induced experimental FM, depend on sex, estrous cycle, ovariectomy and replacement with 17β-estradiol. To fulfill this objective, we compared males, intact females with known estrous cycle phases and ovariectomized (OVX) rats treated with 17β-estradiol. Data demonstrated that reserpine administration disrupted the normal estrous cycle and produced that all females entered metestrus/diestrus. In addition, this treatment leads to muscle hyperalgesia and tactile allodynia in a similar manner in male and intact female rats. However, the absence of ovarian hormones (in OVX rats) increased muscle nociception. 17β-estradiol (2.5-10μg/rat) produced antihyperalgesic and antiallodynic effects 24h, but not 8h, after its administration, suggesting a genomic mechanism. The present results support the validity of the reserpine-induced FM model for searching alternatives of treatment, particularly during endocrine phases when pain is exacerbated such as menopause, and that 17β-estradiol replacement might be useful.
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Affiliation(s)
- Alberto Hernandez-Leon
- Departamento de Farmacobiología, Cinvestav, Unidad Coapa, Calz. De los Tenorios 235, Col. Granjas Coapa, 14330 Mexico City, Mexico; Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México-Xochimilco 101, Col. San Lorenzo, Huipulco, 14370 Mexico City, Mexico
| | - Yarim Elideth De la Luz-Cuellar
- Departamento de Farmacobiología, Cinvestav, Unidad Coapa, Calz. De los Tenorios 235, Col. Granjas Coapa, 14330 Mexico City, Mexico
| | - Vinicio Granados-Soto
- Departamento de Farmacobiología, Cinvestav, Unidad Coapa, Calz. De los Tenorios 235, Col. Granjas Coapa, 14330 Mexico City, Mexico
| | - María Eva González-Trujano
- Dirección de Investigaciones en Neurociencias, Instituto Nacional de Psiquiatría Ramón de la Fuente Muñiz, Calz. México-Xochimilco 101, Col. San Lorenzo, Huipulco, 14370 Mexico City, Mexico
| | - Alonso Fernández-Guasti
- Departamento de Farmacobiología, Cinvestav, Unidad Coapa, Calz. De los Tenorios 235, Col. Granjas Coapa, 14330 Mexico City, Mexico.
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Rosenfeld CS, Shay DA, Vieira-Potter VJ. Cognitive Effects of Aromatase and Possible Role in Memory Disorders. Front Endocrinol (Lausanne) 2018; 9:610. [PMID: 30386297 PMCID: PMC6199361 DOI: 10.3389/fendo.2018.00610] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 09/26/2018] [Indexed: 12/14/2022] Open
Abstract
Diverse cognitive functions in many vertebrate species are influenced by local conversion of androgens to 17β-estradiol (E2) by aromatase. This enzyme is highly expressed in various brain regions across species, with some inter-species variation in terms of regional brain expression. Since women with breast cancer and men and women with other disorders are often treated with aromatase inhibitors (AI), these populations might be especially vulnerable to cognitive deficits due to low neuroE2 synthesis, i.e., synthesis of E2 directly within the brain. Animal models have been useful in deciphering aromatase effects on cognitive functions. Consequences of AI administration at various life cycle stages have been assessed on auditory, song processing, and spatial memory in birds and various aspects of cognition in rodent models. Additionally, cognitive deficits have been described in aromatase knockout (ArKO) mice that systemically lack this gene throughout their lifespan. This review will consider evidence to date that AI treatment in male and female rodent models, birds, and humans results in cognitive impairments. How brain aromatase regulates cognitive function throughout the lifespan, and gaps in current knowledge will be considered, along with future directions to better define how aromatase might guide learning and memory from early development through the geriatric period. Better understanding the importance of E2 synthesis on neurobehavioral responses at various ages will likely aid in the discovery of therapeutic strategies to prevent potential cognitive deficits, including Alzheimer's Disease, in individuals treated with AI or those possessing CYP19 gene polymorphisms, as well as cognitive effects of normal aging that may be related to changes in brain aromatase activity.
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Affiliation(s)
- Cheryl S. Rosenfeld
- Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
- Thompson Center for Autism and Neurobehavioral Disorders, University of Missouri, Columbia, MO, United States
- Biomedical Sciences, University of Missouri, Columbia, MO, United States
- *Correspondence: Cheryl S. Rosenfeld
| | - Dusti A. Shay
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, United States
| | - Victoria J. Vieira-Potter
- Nutrition and Exercise Physiology, University of Missouri, Columbia, MO, United States
- Victoria J. Vieira-Potter
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Plasticity of Signaling by Spinal Estrogen Receptor α, κ-Opioid Receptor, and Metabotropic Glutamate Receptors over the Rat Reproductive Cycle Regulates Spinal Endomorphin 2 Antinociception: Relevance of Endogenous-Biased Agonism. J Neurosci 2017; 37:11181-11191. [PMID: 29025923 DOI: 10.1523/jneurosci.1927-17.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 09/06/2017] [Accepted: 10/02/2017] [Indexed: 01/22/2023] Open
Abstract
We previously showed that intrathecal application of endomorphin 2 [EM2; the highly specific endogenous μ-opioid receptor (MOR) ligand] induces antinociception that varies with stage of the rat estrous cycle: minimal during diestrus and prominent during proestrus. Earlier studies, however, did not identify proestrus-activated signaling strategies that enable spinal EM2 antinociception. We now report that in female rats, increased spinal dynorphin release and κ-opioid receptor (KOR) signaling, as well as the emergence of glutamate-activated metabotropic glutamate receptor 1 (mGluR1) signaling, are critical to the transition from an EM2 nonresponsive state (during diestrus) to an analgesically responsive state (during proestrus). Differential signaling by mGluR1, depending on its activation by membrane estrogen receptor α (mERα; during diestrus) versus glutamate (during proestrus), concomitant with the ebb and flow of spinal dynorphin/KOR signaling, functions as a switch, preventing or promoting, respectively, spinal EM2 antinociception. Importantly, EM2 and glutamate-containing varicosities appose spinal neurons that express MOR along with mGluRs and mERα, suggesting that signaling mechanisms regulating analgesic effectiveness of intrathecally applied EM2 also pertain to endogenous EM2. Regulation of spinal EM2 antinociception by both the nature of the endogenous mGluR1 activator (i.e., endogenous biased agonism at mGluR1) and changes in spinal dynorphin/KOR signaling represent a novel mechanism for modulating analgesic responsiveness to endogenous EM2 (and perhaps other opioids). This points the way for developing noncanonical pharmacological approaches to pain management by harnessing endogenous opioids for pain relief.SIGNIFICANCE STATEMENT The current prescription opioid abuse epidemic underscores the urgency to develop alternative pharmacotherapies for managing pain. We find that the magnitude of spinal endomorphin 2 (EM2) antinociception not only varies with stage of reproductive cycle, but is also differentially regulated during diestrus and proestrus. This finding highlights the need for sex-specific and cycle-specific approaches to pain management. Additionally, our finding that spinal EM2 antinociception in female rats is regulated by both the ebb and flow of spinal dynorphin/κ-opioid receptor signaling over the estrous cycle, as well as the nature of the endogenous mGluR1 activator, could encourage noncanonical pharmacological approaches to pain management, such as harnessing endogenous opioids for pain relief.
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Tran M, Kuhn JA, Bráz JM, Basbaum AI. Neuronal aromatase expression in pain processing regions of the medullary and spinal cord dorsal horn. J Comp Neurol 2017. [PMID: 28649695 DOI: 10.1002/cne.24269] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In both acute and chronic pain conditions, women tend to be more sensitive than men. This sex difference may be regulated by estrogens, such as estradiol, that are synthesized in the spinal cord and brainstem and act locally to influence pain processing. To identify a potential cellular source of local estrogen, here we examined the expression of aromatase, the enzyme that catalyzes the conversion of testosterone to estradiol. Our studies focused on primary afferent neurons and on their central targets in the spinal cord and medulla as well as in the nucleus of the solitary tract, the target of nodose ganglion-derived visceral afferents. Immunohistochemical staining in an aromatase reporter mouse revealed that many neurons in laminae I and V of the spinal cord dorsal horn and caudal spinal trigeminal nucleus and in the nucleus of the solitary tract express aromatase. The great majority of these cells also express inhibitory interneuron markers. We did not find sex differences in aromatase expression and neither the pattern nor the number of neurons changed in a sciatic nerve transection model of neuropathic pain or in the Complete Freund's adjuvant model of inflammatory pain. A few aromatase neurons express Fos after cheek injection of capsaicin, formalin, or chloroquine. In total, given their location, these aromatase neurons are poised to engage nociceptive circuits, whether it is through local estrogen synthesis or inhibitory neurotransmitter release.
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Affiliation(s)
- May Tran
- Department of Anatomy, University of California, San Francisco, San Francisco, California
| | - Julia A Kuhn
- Department of Anatomy, University of California, San Francisco, San Francisco, California
| | - João M Bráz
- Department of Anatomy, University of California, San Francisco, San Francisco, California
| | - Allan I Basbaum
- Department of Anatomy, University of California, San Francisco, San Francisco, California
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30
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Nongenomic Actions of 17-β Estradiol Restore Respiratory Neuroplasticity in Young Ovariectomized Female Rats. J Neurosci 2017; 37:6648-6660. [PMID: 28592693 DOI: 10.1523/jneurosci.0433-17.2017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/18/2017] [Accepted: 05/05/2017] [Indexed: 12/31/2022] Open
Abstract
Gonadal steroids modulate CNS plasticity, including phrenic long-term facilitation (pLTF), a form of spinal respiratory neuroplasticity resulting in increased phrenic nerve motor output following exposure to acute intermittent hypoxia (aIH; three 5 min episodes, 10.5% O2). Despite the importance of respiratory system neuroplasticity, and its dependence on estrogen in males, little is known about pLTF expression or mechanisms of estrogen signaling in females. Here, we tested the hypotheses that (1) pLTF expression in young, gonadally intact female rats would be expressed during estrous cycle stages in which 17β-estradiol (E2) is naturally high (e.g., proestrus vs estrus), (2) pLTF would be absent in ovariectomized (OVX) rats and in physiological conditions in which serum progesterone, but not E2, is elevated (e.g., lactating rats, 3-10 d postpartum), and (3) acute E2 administration would be sufficient to restore pLTF in OVX rats. Recordings of phrenic nerve activity in female Sprague Dawley rats (3-4 months) revealed a direct correlation between serum E2 levels and pLTF expression in cycling female rats. pLTF was abolished with OVX, but was re-established by acute E2 replacement (3 h, intraperitoneal). To identify underlying E2 signaling mechanisms, we intrathecally applied BSA-conjugated E2 over the spinal phrenic motor nucleus and found that pLTF expression was restored within 15 min, suggesting nongenomic E2 effects at membrane estrogen receptors. These data are the first to investigate the role of ovarian E2 in young cycling females, and to identify a role for nongenomic estrogen signaling in any form of respiratory system neuroplasticity.SIGNIFICANCE STATEMENT Exposure to acute intermittent hypoxia induces phrenic long-term facilitation (pLTF), a form of spinal respiratory motor plasticity that improves breathing in models of spinal cord injury. Although pathways leading to pLTF are well studied in males and estradiol (E2) is known to be required, it has seldom been investigated in females, and underlying mechanisms of E2 signaling are unknown in either sex. We found that while ovariectomy abolished pLTF, it could be restored by acute systemic E2, or by intraspinal application of the membrane-impermeable E2 (BSA-conjugated E2; 15 min). The ability of nongenomic estrogen signaling within the cervical spinal cord to recover respiratory neuroplasticity in disorders of respiratory insufficiency suggests that membrane estrogen receptors may represent novel therapeutic targets to restore breathing in both sexes.
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31
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Coronel MF, Labombarda F, González SL. Neuroactive steroids, nociception and neuropathic pain: A flashback to go forward. Steroids 2016; 110:77-87. [PMID: 27091763 DOI: 10.1016/j.steroids.2016.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 03/29/2016] [Accepted: 04/11/2016] [Indexed: 11/26/2022]
Abstract
The present review discusses the potential role of neurosteroids/neuroactive steroids in the regulation of nociceptive and neuropathic pain, and recapitulates the current knowledge on the main mechanisms involved in the reduction of pain, especially those occurring at the dorsal horn of the spinal cord, a crucial site for nociceptive processing. We will make special focus on progesterone and its derivative allopregnanolone, which have been shown to exert remarkable actions in order to prevent or reverse the maladaptive changes and pain behaviors that arise after nervous system damage in various experimental neuropathic conditions.
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Affiliation(s)
- María F Coronel
- Laboratorio de Nocicepción y Dolor Neuropático, Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina; Facultad de Ciencias Biomédicas, Universidad Austral, Presidente Perón 1500, B1629AHJ, Pilar, Buenos Aires, Argentina
| | - Florencia Labombarda
- Laboratorio de Bioquímica Neuroendócrina, Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina; Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG, Buenos Aires, Argentina
| | - Susana L González
- Laboratorio de Nocicepción y Dolor Neuropático, Instituto de Biología y Medicina Experimental, CONICET, Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina; Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, C1121ABG, Buenos Aires, Argentina.
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Robarge JD, Duarte DB, Shariati B, Wang R, Flockhart DA, Vasko MR. Aromatase inhibitors augment nociceptive behaviors in rats and enhance the excitability of sensory neurons. Exp Neurol 2016; 281:53-65. [PMID: 27072527 DOI: 10.1016/j.expneurol.2016.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/28/2016] [Accepted: 04/05/2016] [Indexed: 12/22/2022]
Abstract
Although aromatase inhibitors (AIs) are commonly used therapies for breast cancer, their use is limited because they produce arthralgia in a large number of patients. To determine whether AIs produce hypersensitivity in animal models of pain, we examined the effects of the AI, letrozole, on mechanical, thermal, and chemical sensitivity in rats. In ovariectomized (OVX) rats, administering a single dose of 1 or 5mg/kg letrozole significantly reduced mechanical paw withdrawal thresholds, without altering thermal sensitivity. Repeated injection of 5mg/kg letrozole in male rats produced mechanical, but not thermal, hypersensitivity that extinguished when drug dosing was stopped. A single dose of 5mg/kg letrozole or daily dosing of letrozole or exemestane in male rats also augmented flinching behavior induced by intraplantar injection of 1000nmol of adenosine 5'-triphosphate (ATP). To determine whether sensitization of sensory neurons contributed to AI-induced hypersensitivity, we evaluated the excitability of neurons isolated from dorsal root ganglia of male rats chronically treated with letrozole. Both small and medium-diameter sensory neurons isolated from letrozole-treated rats were more excitable, as reflected by increased action potential firing in response to a ramp of depolarizing current, a lower resting membrane potential, and a lower rheobase. However, systemic letrozole treatment did not augment the stimulus-evoked release of the neuropeptide calcitonin gene-related peptide (CGRP) from spinal cord slices, suggesting that the enhanced nociceptive responses were not secondary to an increase in peptide release from sensory endings in the spinal cord. These results provide the first evidence that AIs modulate the excitability of sensory neurons, which may be a primary mechanism for the effect of these drugs to augment pain behaviors in rats.
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Affiliation(s)
- Jason D Robarge
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States; Department of Medicine, Division of Clinical Pharmacology, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - Djane B Duarte
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States; Laboratório de Farmacologia Molecular, Faculdade de Ciências da Saúde, Universidade de Brasília, Brazil.
| | - Behzad Shariati
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - Ruizhong Wang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - David A Flockhart
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States; Department of Medicine, Division of Clinical Pharmacology, Indiana University School of Medicine, Indianapolis, IN, United States.
| | - Michael R Vasko
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States.
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33
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Lower sex hormone levels are associated with more chronic musculoskeletal pain in community-dwelling elderly women. Pain 2016; 157:1425-1431. [DOI: 10.1097/j.pain.0000000000000535] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Vacca V, Marinelli S, Pieroni L, Urbani A, Luvisetto S, Pavone F. 17beta-estradiol counteracts neuropathic pain: a behavioural, immunohistochemical, and proteomic investigation on sex-related differences in mice. Sci Rep 2016; 6:18980. [PMID: 26742647 PMCID: PMC4705539 DOI: 10.1038/srep18980] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 09/02/2015] [Indexed: 01/31/2023] Open
Abstract
Sex differences play a role in pain sensitivity, efficacy of analgesic drugs and prevalence of neuropathic pain, even if the underlying mechanisms are far from being understood. We demonstrate that male and female mice react differently to structural and functional changes induced by sciatic nerve ligature, used as model of neuropathic pain. Male mice show a gradual decrease of allodynia and a complete recovery while, in females, allodynia and gliosis are still present four months after neuropathy induction. Administration of 17β-estradiol is able to significantly attenuate this difference, reducing allodynia and inducing a complete recovery also in female mice. Parallel to pain attenuation, 17β-estradiol treated-mice show a functional improvement of the injured limb, a faster regenerative process of the peripheral nerve and a decreased neuropathy-induced gliosis. These results indicate beneficial effects of 17β-estradiol on neuropathic pain and neuronal regeneration and focuses on the importance of considering gonadal hormones also in clinical studies.
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Affiliation(s)
- Valentina Vacca
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, 00143 Roma, Italy.,IRCCS Fondazione Santa Lucia, 00143 Roma, Italy
| | - Sara Marinelli
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, 00143 Roma, Italy.,IRCCS Fondazione Santa Lucia, 00143 Roma, Italy
| | - Luisa Pieroni
- IRCCS Fondazione Santa Lucia, 00143 Roma, Italy.,Department of Experimental Medicine and Surgery, Division of Biochemistry, University of "Tor Vergata", 00133 Roma, Italy
| | - Andrea Urbani
- IRCCS Fondazione Santa Lucia, 00143 Roma, Italy.,Department of Experimental Medicine and Surgery, Division of Biochemistry, University of "Tor Vergata", 00133 Roma, Italy
| | - Siro Luvisetto
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, 00143 Roma, Italy.,IRCCS Fondazione Santa Lucia, 00143 Roma, Italy
| | - Flaminia Pavone
- CNR-National Research Council, Institute of Cell Biology and Neurobiology, 00143 Roma, Italy.,IRCCS Fondazione Santa Lucia, 00143 Roma, Italy
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35
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Fuxjager MJ, Schlinger BA. Perspectives on the evolution of animal dancing: a case study of manakins. Curr Opin Behav Sci 2015. [DOI: 10.1016/j.cobeha.2015.06.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Abstract
Sex differences in the prevalence of painful conditions appear after pubertyVariation in symptom severity across the menstrual cycle occurs in a number of clinical pain conditionsSex steroid hormones act at a number of sites in both the peripheral and central nervous systems and in both reproductive and non-reproductive tissuesSex steroid hormones have traditionally been thought to alter transcription; however, there is evidence that there are also non-genomic effectsSex steroid hormones can have organisational effects from as early as in uteroThe relationship between sex hormones and pain is complex.
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Affiliation(s)
- Katy Vincent
- Research Fellow, Functional Magnetic Resonance Imaging of the Brain Centre, John Radcliffe Hospital, Oxford
| | - Irene Tracey
- Professor, Functional Magnetic Resonance Imaging of the Brain Centre, John Radcliffe Hospital, Oxford
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O'Brien EE, Smeester BA, Michlitsch KS, Lee JH, Beitz AJ. Colocalization of aromatase in spinal cord astrocytes: differences in expression and relationship to mechanical and thermal hyperalgesia in murine models of a painful and a non-painful bone tumor. Neuroscience 2015; 301:235-45. [PMID: 26071956 DOI: 10.1016/j.neuroscience.2015.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 12/14/2022]
Abstract
While spinal cord astrocytes play a key role in the generation of cancer pain, there have been no studies that have examined the relationship of tumor-induced astrocyte activation and aromatase expression during the development of cancer pain. Here, we examined tumor-induced mechanical hyperalgesia and cold allodynia, and changes in Glial fibrillary acid protein (GFAP) and aromatase expression in murine models of painful and non-painful bone cancer. We demonstrate that implantation of fibrosarcoma cells, but not melanoma cells, produces robust mechanical hyperalgesia and cold allodynia in tumor-bearing mice compared to saline-injected controls. Secondly, this increase in mechanical hyperalgesia and cold allodynia is mirrored by significant increases in both spinal astrocyte activity and aromatase expression in the dorsal horn of fibrosarcoma-bearing mice. Importantly, we show that aromatase is only found within a subset of astrocytes and not in neurons in the lumbar spinal cord. Finally, administration of an aromatase inhibitor reduced tumor-induced hyperalgesia in fibrosarcoma-bearing animals. We conclude that a painful fibrosarcoma tumor induces a significant increase in spinal astrocyte activation and aromatase expression and that the up-regulation of aromatase plays a role in the development of bone tumor-induced hyperalgesia. Since spinal aromatase is also upregulated, but to a lesser extent, in non-painful melanoma bone tumors, it may also be neuroprotective and responsive to the changing tumor environment.
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Affiliation(s)
- E E O'Brien
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - B A Smeester
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - K S Michlitsch
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
| | - J-H Lee
- Department of Veterinary Physiology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 151-742, Republic of Korea
| | - A J Beitz
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, 1971 Commonwealth Avenue, St. Paul, MN 55108, USA.
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Fuxjager MJ, Eaton J, Lindsay WR, Salwiczek LH, Rensel MA, Barske J, Sorenson L, Day LB, Schlinger BA. Evolutionary patterns of adaptive acrobatics and physical performance predict expression profiles of androgen receptor - but not oestrogen receptor - in the forelimb musculature. Funct Ecol 2015; 29:1197-1208. [PMID: 26538789 DOI: 10.1111/1365-2435.12438] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
1. Superior physical competence is vital to the adaptive behavioral routines of many animals, particularly those that engage in elaborate socio-sexual displays. How such traits evolve across species remains unclear. 2. Recent work suggests that activation of sex steroid receptors in neuromuscular systems is necessary for the fine motor skills needed to execute physically elaborate displays. Thus, using passerine birds as models, we test whether interspecific variation in display complexity predicts species differences in the abundance of androgen and estrogen receptors (AR and ERα) expressed in the forelimb musculature and spinal cord. 3. We find that small-scale evolutionary patterns in physical display complexity positively predict expression of the AR in the main muscles that lift and retract the wings. No such relationship is detected in the spinal cord, and we do not find a correlation between display behavior and neuromuscular expression of ERα. Also, we find that AR expression levels in different androgen targets throughout the body - namely the wing muscles, spinal cord, and testes - are not necessarily correlated, providing evidence that evolutionary forces may drive AR expression in a tissue-specific manner. 4. These results suggest co-evolution between the physical prowess necessary for display performance and levels of AR expression in avian forelimb muscles. Moreover, this relationship appears to be specific to muscle and AR-mediated, but not ERα-mediated, signaling. 5. Given that prior work suggests that activation of muscular AR is a necessary component of physical display performance, our current data support the hypothesis that sexual selection shapes levels of AR expressed in the forelimb skeletal muscles to help drive the evolution of adaptive motor abilities.
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Affiliation(s)
- Matthew J Fuxjager
- Department of Biology, Wake Forest University, 228 Winston Hall, Winston-Salem, NC 27109, USA ; Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA ; Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Joy Eaton
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Willow R Lindsay
- Department of Biology, University of Mississippi, University, MS 38677, USA
| | - Lucie H Salwiczek
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA ; Department of Behavioral Neurobiology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | - Michelle A Rensel
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Julia Barske
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Laurie Sorenson
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Lainy B Day
- Department of Biology, University of Mississippi, University, MS 38677, USA
| | - Barney A Schlinger
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA ; Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA ; Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095, USA ; Smithsonian Tropical Research Institute, Apartado Postal 0843-03092, Balboa, Ancón, Panama
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Kumar A, Storman EM, Liu NJ, Gintzler AR. Estrogens Suppress Spinal Endomorphin 2 Release in Female Rats in Phase with the Estrous Cycle. Neuroendocrinology 2015; 102:33-43. [PMID: 25925013 PMCID: PMC4575620 DOI: 10.1159/000430817] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 04/20/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND/AIMS Male and female rats differ in their ability to utilize spinal endomorphin 2 (EM2; the predominant mu-opioid receptor ligand in spinal cord) and in the mechanisms that underlie spinal EM2 analgesic responsiveness. We investigated the relevance of spinal estrogen receptors (ERs) to the in vivo regulation of spinal EM2 release. METHODS ER antagonists were administered directly to the lumbosacral spinal cord of male and female rats, intrathecal perfusate was collected, and resulting changes in EM2 release were quantified using a plate-based radioimmunoassay. RESULTS Intrathecal application of an antagonist of either estrogen receptor-α (ERα) or the ER GPR30 failed to alter spinal EM2 release. Strikingly, however, the concomitant blockade of ERα and GPR30 enhanced spinal EM2 release. This effect was sexually dimorphic, being absent in males. Furthermore, the magnitude of the enhancement of spinal EM2 release in females was dependent upon estrous cycle stage, suggesting a relationship with circulating levels of 17β-estradiol. The rapid onset of enhanced EM2 release following intrathecal application of ERα/GPR30 antagonists (within 30-40 min) suggests mediation via ERs in the plasma membrane, not the nucleus. Notably, both ovarian and spinally synthesized estrogens are essential for membrane ER regulation of spinal EM2 release. CONCLUSION These findings underscore the importance of estrogens for the regulation of spinal EM2 activity and, by extension, endogenous spinal EM2 antinociception in females. Components of the spinal estrogenic mechanism(s) that suppress EM2 release could represent novel drug targets for improving utilization of endogenous spinal EM2, and thereby pain management in women.
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Affiliation(s)
- Arjun Kumar
- Department of Obstetrics and Gynecology, State University of New York, Downstate Medical Center, Brooklyn, N.Y., USA
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40
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Ghorbanpoor S, Garcia-Segura LM, Haeri-Rohani A, Khodagholi F, Jorjani M. Aromatase inhibition exacerbates pain and reactive gliosis in the dorsal horn of the spinal cord of female rats caused by spinothalamic tract injury. Endocrinology 2014; 155:4341-55. [PMID: 25105782 DOI: 10.1210/en.2014-1158] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Central pain syndrome is characterized by severe and excruciating pain resulting from a lesion in the central nervous system. Previous studies have shown that estradiol decreases pain and that inhibitors of the enzyme aromatase, which synthesizes estradiol from aromatizable androgens, increases pain sensitivity. In this study we have assessed whether aromatase expression in the dorsal horns of the spinal cord is altered in a rat model of central pain syndrome, induced by the unilateral electrolytic lesion of the spinothalamic tract. Protein and mRNA levels of aromatase, as well as the protein and mRNA levels of estrogen receptors α and β, were increased in the dorsal horn of female rats after spinothalamic tract injury, suggesting that the injury increased estradiol synthesis and signaling in the dorsal horn. To determine whether the increased aromatase expression in this pain model may participate in the control of pain, mechanical allodynia thresholds were determined in both hind paws after the intrathecal administration of letrozole, an aromatase inhibitor. Aromatase inhibition enhanced mechanical allodynia in both hind paws. Because estradiol is known to regulate gliosis we assessed whether the spinothalamic tract injury and aromatase inhibition regulated gliosis in the dorsal horn. The proportion of microglia with a reactive phenotype and the number of glial fibrillary acidic protein-immunoreactive astrocytes were increased by the injury in the dorsal horn. Aromatase inhibition enhanced the effect of the injury on gliosis. Furthermore, a significant a positive correlation of mechanical allodynia and gliosis in the dorsal horn was detected. These findings suggest that aromatase is up-regulated in the dorsal horn in a model of central pain syndrome and that aromatase activity in the spinal cord reduces mechanical allodynia by controlling reactive gliosis in the dorsal horn.
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Affiliation(s)
- Samar Ghorbanpoor
- Department of Cell and Molecular Biology (S.G.), Department of Animal Biology (A.H.-R.), School of Biology, College of Science (S.G.), University of Tehran, Tehran, Iran; Consejo Superior de Investigaciones Científicas (L.M.G.-S.), Instituto Cajal, E-28002 Madrid, Spain; Neurobiology Research Center (F.K., M.J.), Shahid Beheshti University of Medical Sciences, Tehran, Iran; and Department of Pharmacology, Faculty of Medicine (M.J.), Shahid Beheshti University of Medical Sciences, Tehran, Iran
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41
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Abstract
Emerging research has demonstrated that the sex hormone estradiol regulates fear extinction in female rodents and women. Estradiol may also regulate fear extinction in males, given its role in synaptic plasticity in both sexes. Here we report that inhibition of estradiol synthesis during extinction training, via the aromatase inhibitor fadrozole, significantly impairs extinction recall in male rats. This deficit in extinction recall is not due to state-dependent memory formation and is completely abolished by coadministration of estradiol. Our data suggest that estradiol may be just as important in the regulation of fear extinction in males as it is in females.
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Affiliation(s)
- Bronwyn M Graham
- Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Mohammed R Milad
- Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
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42
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An G, Li W, Yan T, Li S. Estrogen rapidly enhances incisional pain of ovariectomized rats primarily through the G protein-coupled estrogen receptor. Int J Mol Sci 2014; 15:10479-91. [PMID: 24921706 PMCID: PMC4100163 DOI: 10.3390/ijms150610479] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Revised: 05/10/2014] [Accepted: 05/13/2014] [Indexed: 01/24/2023] Open
Abstract
It has become increasingly apparent that the pain threshold of females and males varies in an estrogen dependent manner. To investigate the modulation of pain by estrogen and the molecular mechanisms involved in this process. A total of 48 rats were ovariectomized (OVX). At 14 and 20 days after OVX, rats were divided into eight groups: groups 1–4 were administered drugs intravenously (IV); groups 5–8 were administered through intrathecal (IT) catheter. Hind paw incision was made in all animals to determine incisional pain. Paw withdraw threshold (PWT) was tested prior to and 24 h after incision. The test drugs were applied 24 h after the incision. Rats were either IV or IT administered with: 17-β-estradiol (E2), G protein-coupled estrogen receptor (GPER)-selective agonist (G1), GPER-selective antagonist (G15) and E2 (G15 + E2), or solvent. Before and 30 min after IV drug administration and 20 min during the IT catheter administration, PWT was tested and recorded. 24 h after incisional surgery, the PWT of all rats significantly decreased. Both in the IV group and IT group: administration of E2 and G1 significantly decreased PWT. Neither administration of G15 + E2 nor solvent significantly changed PWT. Estrogen causes rapid reduction in the mechanical pain threshold of OVX rats via GPER.
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Affiliation(s)
- Guanghui An
- Department of Anesthesiology, Shanghai First People's Hospital, Shanghai 200080, China.
| | - Wenhui Li
- Department of Anesthesiology, Obstetrics and Gynecology Hospital of Fudan University, Shanghai 200090, China.
| | - Tao Yan
- Department of Anesthesiology, Shanghai First People's Hospital, Shanghai 200080, China.
| | - Shitong Li
- Department of Anesthesiology, Shanghai First People's Hospital, Shanghai 200080, China.
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43
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Aloisi AM, Sorda G. Relationship of female sex hormones with pain perception: focus on estrogens. Pain Manag 2014; 1:229-38. [PMID: 24646389 DOI: 10.2217/pmt.11.13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY The role of gonadal hormones has slowly gathered the right attention in the study of chronic pain mechanisms. The clear presence of sex differences in chronic pain and the number of studies showing the power of gonadal hormones to modify pain-induced behavioral responses appear to have convinced clinicians and researchers. Indeed, available data strongly indicate that more studies on gonadal hormones would certainly enhance the possibility of greatly increasing the knowledge of pain mechanisms and, thus, treatments. In the present article, old and new literature are summarized to evaluate data on pain and its modulation by gonadal hormones, particularly estrogens. Peripheral and central targets of these hormones are discussed with the aim of renewing interest in important aspects of estrogenic functions and their interactions with pain processes.
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Affiliation(s)
- Anna Maria Aloisi
- San Carlo Clinic, via dell'Ospedale 21, Paderno Dugnano Milano, Italy; Neurophysiology of Stress & Pain Laboratory, Department of Physiology, Polo Scientifico San Miniato, Via Aldo Moro 2, 53100 Siena, Italy
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44
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Amandusson Å, Blomqvist A. Estrogenic influences in pain processing. Front Neuroendocrinol 2013; 34:329-49. [PMID: 23817054 DOI: 10.1016/j.yfrne.2013.06.001] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Revised: 06/19/2013] [Accepted: 06/20/2013] [Indexed: 12/24/2022]
Abstract
Gonadal hormones not only play a pivotal role in reproductive behavior and sexual differentiation, they also contribute to thermoregulation, feeding, memory, neuronal survival, and the perception of somatosensory stimuli. Numerous studies on both animals and human subjects have also demonstrated the potential effects of gonadal hormones, such as estrogens, on pain transmission. These effects most likely involve multiple neuroanatomical circuits as well as diverse neurochemical systems and they therefore need to be evaluated specifically to determine the localization and intrinsic characteristics of the neurons engaged. The aim of this review is to summarize the morphological as well as biochemical evidence in support for gonadal hormone modulation of nociceptive processing, with particular focus on estrogens and spinal cord mechanisms.
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Affiliation(s)
- Åsa Amandusson
- Department of Clinical Neurophysiology, Uppsala University, 751 85 Uppsala, Sweden.
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45
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Lee KS, Asgar J, Zhang Y, Chung MK, Ro JY. The role of androgen receptor in transcriptional modulation of cannabinoid receptor type 1 gene in rat trigeminal ganglia. Neuroscience 2013; 254:395-403. [PMID: 24055403 DOI: 10.1016/j.neuroscience.2013.09.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 09/04/2013] [Accepted: 09/05/2013] [Indexed: 12/31/2022]
Abstract
We have previously shown that anti-hyperalgesic effects of cannabinoid agonists under inflammatory condition are much greater in male than female, and that inflammatory cytokines upregulate cannabinoid receptor type 1 (CB1) expression in male, but not female, trigeminal ganglia (TG) in a testosterone-dependent manner. In this study, we investigated the mechanisms underlying the testosterone-mediated regulation of peripheral CB1 expression. We hypothesized that testosterone upregulates CB1 through transcriptional modulation by androgen receptor (AR). Interleukin-1 beta (IL-1β), a pro-inflammatory cytokine, upregulated CB1 mRNA expression in TG of male rats. The cytokine-induced upregulation was prevented by the pretreatment with flutamide, a specific antagonist for AR, but not by ICI 182,780, a specific antagonist for estrogen receptor, suggesting that the effects of testosterone are not mediated by estradiol, a testosterone metabolite. The expression levels of AR and IL-1β receptors were comparable between male and female TG, suggesting that the male specific IL-1β effects on CB1 upregulation occurs downstream to these receptors. The chromatin immunoprecipitation assay showed AR binding to the CB1 promoter in the rat TG. Furthermore, luciferase reporter assay revealed that AR activated the CB1 gene in response to testosterone or dihydrotestosterone treatment. These experiments provided compelling evidence that testosterone regulates CB1 gene transcription in TG through AR following cytokine stimulation. These results should provide mechanistic bases for understanding cytokine-hormone-neuron interactions in peripheral cannabinoid systems, and have important clinical implications for pain patients in whom testosterone level is naturally low, gradually declining or pharmacologically compromised.
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Affiliation(s)
- K S Lee
- University of Maryland Dental School, Department of Neural and Pain Sciences, Program in Neuroscience, Baltimore, MD 21201, USA
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46
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Cornil CA, Ball GF, Balthazart J. Rapid control of male typical behaviors by brain-derived estrogens. Front Neuroendocrinol 2012; 33:425-46. [PMID: 22983088 PMCID: PMC3496013 DOI: 10.1016/j.yfrne.2012.08.003] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/13/2012] [Accepted: 08/17/2012] [Indexed: 01/01/2023]
Abstract
Beside their genomic mode of action, estrogens also activate a variety of cellular signaling pathways through non-genomic mechanisms. Until recently, little was known regarding the functional significance of such actions in males and the mechanisms that control local estrogen concentration with a spatial and time resolution compatible with these non-genomic actions had rarely been examined. Here, we review evidence that estrogens rapidly modulate a variety of behaviors in male vertebrates. Then, we present in vitro work supporting the existence of a control mechanism of local brain estrogen synthesis by aromatase along with in vivo evidence that rapid changes in aromatase activity also occur in a region-specific manner in response to changes in the social or environmental context. Finally, we suggest that the brain estrogen provision may also play a significant role in females. Together these data bolster the hypothesis that brain-derived estrogens should be considered as neuromodulators.
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Affiliation(s)
- Charlotte A Cornil
- GIGA Neurosciences, Research Group in Behavioral Neuroendocrinology, University of Liège, Liège, Belgium.
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47
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Gintzler AR, Liu NJ. Importance of sex to pain and its amelioration; relevance of spinal estrogens and its membrane receptors. Front Neuroendocrinol 2012; 33:412-24. [PMID: 23036438 PMCID: PMC3778676 DOI: 10.1016/j.yfrne.2012.09.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 09/13/2012] [Accepted: 09/18/2012] [Indexed: 12/14/2022]
Abstract
Estrogens have a multitude of effects on opioid systems and are thought to play a key role in sexually dimorphic nociception and opioid antinociception. Heretofore, classical genomic actions of estrogens are largely thought to be responsible for the effects of these steroids on nociception and opioid antinociception. The recent discovery that estrogens can also activate estrogen receptors that are located in the plasma membrane, the effects of which are manifest in seconds to minutes instead of hours to days has revolutionized our thinking concerning the ways in which estrogens are likely to modulate pain responsiveness and the dynamic nature of that modulation. This review summarizes parameters of opioid functionality and nociception that are subject to modulation by estrogens, underscoring the added dimensions of such modulation that accrues from rapid membrane estrogen receptor signaling. Implications of this mode of signaling regarding putative sources of estrogens and its degradation are also discussed.
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Affiliation(s)
- Alan R Gintzler
- State University of New York, Downstate Medical Center, 450 Clarkson Ave., Brooklyn, NY 11203, USA.
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48
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Zhang Y, Lü N, Zhao ZQ, Zhang YQ. Involvement of estrogen in rapid pain modulation in the rat spinal cord. Neurochem Res 2012; 37:2697-705. [PMID: 22903468 DOI: 10.1007/s11064-012-0859-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Revised: 07/17/2012] [Accepted: 07/28/2012] [Indexed: 12/16/2022]
Abstract
The pivotal role of estrogens in the pain sensitivity has been investigated in many ways. Traditionally, it is ascribed to the slow genomic changes mediated by classical nuclear estrogen receptors (ER), ERα and ERβ, depending on peripheral estrogens. Recently, it has become clear that estrogens can also signal through membrane ERs (mERs), such as G-protein-coupled ER1 (GPER1), mediating the non-genomic effects. However, the spinal specific role played by ERs and the underlying cellular mechanisms remain elusive. The present study investigated the rapid estrogenic regulation of nociception at the spinal level. Spinal administration of 17β-estradiol (E2), the most potent natural estrogen, acutely produced a remarkable mechanical allodynia and thermal hyperalgesia without significant differences among male, female and ovariectomized (Ovx) rats. E2-induced the pro-nociceptive effects were partially abrogated by ICI 182,780 (ERs antagonist), and mimicked by E2-BSA (a mER agonist). Inhibition of local E2 synthesis by 1,4,6-Androstatrien-3,17-dione (ATD, a potent irreversible aromatase inhibitor), or blockade of ERs by ICI 182,780 produced an inhibitory effect on the late phase of formalin nociceptive responses. Notably, lumbar puncture injection of G15 (a selective GPER1 antagonist) resulted in similar but more efficient inhibition of formalin nociceptive responses as compared with ICI 182,780. At the cellular level, the amplitude and decay time of spontaneous inhibitory postsynaptic currents were attenuated by short E2 or E2-BSA treatment in spinal slices. These results indicate that estrogen acutely facilitates nociceptive transmission in the spinal cord via activation of membrane-bound estrogen receptors.
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Affiliation(s)
- Yan Zhang
- Institute of Neurobiology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032, China
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49
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Zhang Y, Xiao X, Zhang XM, Zhao ZQ, Zhang YQ. Estrogen facilitates spinal cord synaptic transmission via membrane-bound estrogen receptors: implications for pain hypersensitivity. J Biol Chem 2012; 287:33268-81. [PMID: 22869379 DOI: 10.1074/jbc.m112.368142] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Recent evidence suggests that estrogen is synthesized in the spinal dorsal horn and plays a role in nociceptive processes. However, the cellular and molecular mechanisms underlying these effects remain unclear. Using electrophysiological, biochemical, and morphological techniques, we here demonstrate that 17β-estradiol (E2), a major form of estrogen, can directly modulate spinal cord synaptic transmission by 1) enhancing NMDA receptor-mediated synaptic transmission in dorsal horn neurons, 2) increasing glutamate release from primary afferent terminals, 3) increasing dendritic spine density in cultured spinal cord dorsal horn neurons, and 4) potentiating spinal cord long term potentiation (LTP) evoked by high frequency stimulation (HFS) of Lissauer's tract. Notably, E2-BSA, a ligand that acts only on membrane estrogen receptors, can mimic E2-induced facilitation of HFS-LTP, suggesting a nongenomic action of this neurosteroid. Consistently, cell surface biotinylation demonstrated that three types of ERs (ERα, ERβ, and GPER1) are localized on the plasma membrane of dorsal horn neurons. Furthermore, the ERα and ERβ antagonist ICI 182,780 completely abrogates the E2-induced facilitation of LTP. ERβ (but not ERα) activation can recapitulate E2-induced persistent increases in synaptic transmission (NMDA-dependent) and dendritic spine density, indicating a critical role of ERβ in spinal synaptic plasticity. E2 also increases the phosphorylation of ERK, PKA, and NR2B, and spinal HFS-LTP is prevented by blockade of PKA, ERK, or NR2B activation. Finally, HFS increases E2 release in spinal cord slices, which can be prevented by aromatase inhibitor androstatrienedione, suggesting activity-dependent local synthesis and release of endogenous E2.
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Affiliation(s)
- Yan Zhang
- Institute of Neurobiology, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200032, China
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50
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Fuxjager MJ, Schultz JD, Barske J, Feng NY, Fusani L, Mirzatoni A, Day LB, Hau M, Schlinger BA. Spinal motor and sensory neurons are androgen targets in an acrobatic bird. Endocrinology 2012; 153:3780-91. [PMID: 22635677 PMCID: PMC5393326 DOI: 10.1210/en.2012-1313] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Sex steroids affect the motivation to court mates, but less is known about how they influence motor movements associated with courtship behavior. Steroidal control of motor function may be especially important for species in which courtship requires superior strength, stamina, and neuromuscular coordination. Here we use the golden-collared manakin (Manacus vitellinus) to examine whether the neuromuscular circuitry that controls motoric aspects of courtship activity is sensitive to androgens. Males of this tropical species attract mates by rapidly jumping among branches in a courtship arena and using their wings to produce loud wing snaps. Testosterone activates this display via the androgen receptor (AR), and past work reveals that manakins injected with radio-labeled T ((3)H-T) accumulate radioactivity in the spinal cord. Thus, we used quantitative PCR to measure AR, estrogen receptor-α (ER-α) subtype, and aromatase (AROM) mRNA in spinal cords of male and female manakins and zebra finches. Expression of AR, but not ER-α or aromatase, was higher throughout the manakin spinal cord compared with the zebra finch. Next, we tested whether AR-expressing skeletal muscles are innervated by motor and sensory neurons that also express AR. To do this, we backfilled spinal neurons by injecting fluorescent tracers into select AR-sensitive wing and leg muscles of wild caught male and female manakins. We then removed these spinal cords and measured AR expression with in situ hybridization. Both sexes showed abundant AR mRNA in the cervical and lumbosacral spinal enlargements as well as in dorsal root ganglia attached to these enlargements. Together our findings suggest that androgens act widely on peripheral motor and sensory circuits in golden-collared manakins to influence wing snapping displays.
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Affiliation(s)
- Matthew J Fuxjager
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, California 90095-7239, USA
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