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Cervera-Juanes R, Zimmerman KD, Wilhelm L, Zhu D, Bodie J, Kohama SG, Urbanski HF. Modulation of neural gene networks by estradiol in old rhesus macaque females. GeroScience 2024:10.1007/s11357-024-01133-z. [PMID: 38509416 DOI: 10.1007/s11357-024-01133-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: 01/08/2024] [Accepted: 03/12/2024] [Indexed: 03/22/2024] Open
Abstract
The postmenopausal decrease in circulating estradiol (E2) levels has been shown to contribute to several adverse physiological and psychiatric effects. To elucidate the molecular effects of E2 on the brain, we examined differential gene expression and DNA methylation (DNAm) patterns in the nonhuman primate brain following ovariectomy (Ov) and subsequent subcutaneous bioidentical E2 chronic treatment. We identified several dysregulated molecular networks, including MAPK signaling and dopaminergic synapse response, that are associated with ovariectomy and shared across two different brain areas, the occipital cortex (OC) and prefrontal cortex (PFC). The finding that hypomethylation (p = 1.6 × 10-51) and upregulation (p = 3.8 × 10-3) of UBE2M across both brain regions provide strong evidence for molecular differences in the brain induced by E2 depletion. Additionally, differential expression (p = 1.9 × 10-4; interaction p = 3.5 × 10-2) of LTBR in the PFC provides further support for the role E2 plays in the brain, by demonstrating that the regulation of some genes that are altered by ovariectomy may also be modulated by Ov followed by hormone replacement therapy (HRT). These results present real opportunities to understand the specific biological mechanisms that are altered with depleted E2. Given E2's potential role in cognitive decline and neuroinflammation, our findings could lead to the discovery of novel therapeutics to slow cognitive decline. Together, this work represents a major step toward understanding molecular changes in the brain that are caused by ovariectomy and how E2 treatment may revert or protect against the negative neuro-related consequences caused by a depletion in estrogen as women approach menopause.
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Affiliation(s)
- Rita Cervera-Juanes
- Department of Translational Neuroscience, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA.
- Center for Precision Medicine, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA.
| | - Kip D Zimmerman
- Center for Precision Medicine, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA
- Department of Internal Medicine, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Larry Wilhelm
- Department of Translational Neuroscience, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Dongqin Zhu
- Department of Translational Neuroscience, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Jessica Bodie
- Department of Translational Neuroscience, Wake Forest University School of Medicine, 1 Medical Center Boulevard, Winston-Salem, NC, 27157, USA
| | - Steven G Kohama
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, 97006, USA
| | - Henryk F Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, 97006, USA
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Beaverton, OR, 97006, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, 97239, USA
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Cervera-Juanes R, Zimmerman KD, Wilhelm L, Zhu D, Bodie J, Kohama SG, Urbanski HF. Modulation of neural gene networks by estradiol in old rhesus macaque females. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572105. [PMID: 38187564 PMCID: PMC10769303 DOI: 10.1101/2023.12.18.572105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The postmenopausal decrease in circulating estradiol (E2) levels has been shown to contribute to several adverse physiological and psychiatric effects. To elucidate the molecular effects of E2 on the brain, we examined differential gene expression and DNA methylation (DNAm) patterns in the nonhuman primate brain following ovariectomy (Ov) and subsequent E2 treatment. We identified several dysregulated molecular networks, including MAPK signaling and dopaminergic synapse response, that are associated with ovariectomy and shared across two different brain areas, the occipital cortex (OC) and prefrontal cortex (PFC). The finding that hypomethylation (p=1.6×10-51) and upregulation (p=3.8×10-3) of UBE2M across both brain regions, provide strong evidence for molecular differences in the brain induced by E2 depletion. Additionally, differential expression (p=1.9×10-4; interaction p=3.5×10-2) of LTBR in the PFC, provides further support for the role E2 plays in the brain, by demonstrating that the regulation of some genes that are altered by ovariectomy may also be modulated by Ov followed by hormone replacement therapy (HRT). These results present real opportunities to understand the specific biological mechanisms that are altered with depleted E2. Given E2's potential role in cognitive decline and neuroinflammation, our findings could lead to the discovery of novel therapeutics to slow cognitive decline. Together, this work represents a major step towards understanding molecular changes in the brain that are caused by ovariectomy and how E2 treatment may revert or protect against the negative neuro-related consequences caused by a depletion in estrogen as women approach menopause.
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Affiliation(s)
- Rita Cervera-Juanes
- Department of Translational Neuroscience, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
- Center for Precision Medicine, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
| | - Kip D. Zimmerman
- Center for Precision Medicine, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
- Department of Internal Medicine, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
| | - Larry Wilhelm
- Department of Translational Neuroscience, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
| | - Dongqin Zhu
- Department of Translational Neuroscience, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
| | - Jessica Bodie
- Department of Translational Neuroscience, Atrium Health Wake Forest Baptist, Winston-Salem, NC 27157
| | - Steven G. Kohama
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon, USA
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, Oregon, USA
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Beaverton, Oregon, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon, USA
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Daniel JM, Lindsey SH, Mostany R, Schrader LA, Zsombok A. Cardiometabolic health, menopausal estrogen therapy and the brain: How effects of estrogens diverge in healthy and unhealthy preclinical models of aging. Front Neuroendocrinol 2023; 70:101068. [PMID: 37061205 PMCID: PMC10725785 DOI: 10.1016/j.yfrne.2023.101068] [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: 02/16/2023] [Revised: 03/23/2023] [Accepted: 04/10/2023] [Indexed: 04/17/2023]
Abstract
Research in preclinical models indicates that estrogens are neuroprotective and positively impact cognitive aging. However, clinical data are equivocal as to the benefits of menopausal estrogen therapy to the brain and cognition. Pre-existing cardiometabolic disease may modulate mechanisms by which estrogens act, potentially reducing or reversing protections they provide against cognitive decline. In the current review we propose mechanisms by which cardiometabolic disease may alter estrogen effects, including both alterations in actions directly on brain memory systems and actions on cardiometabolic systems, which in turn impact brain memory systems. Consideration of mechanisms by which estrogen administration can exert differential effects dependent upon health phenotype is consistent with the move towards precision or personalized medicine, which aims to determine which treatment interventions will work for which individuals. Understanding effects of estrogens in both healthy and unhealthy models of aging is critical to optimizing the translational link between preclinical and clinical research.
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Affiliation(s)
- Jill M Daniel
- Department of Psychology and Brain Institute, Tulane University, New Orleans, LA, United States.
| | - Sarah H Lindsey
- Department of Pharmacology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Ricardo Mostany
- Department of Pharmacology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Laura A Schrader
- Department of Cell & Molecular Biology and Brain Institute, Tulane University, New Orleans, LA, United States
| | - Andrea Zsombok
- Department of Physiology and Brain Institute, Tulane University, New Orleans, LA, United States
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Suzuki YI, Shibuya K, Misawa S, Suichi T, Tsuneyama A, Kojima Y, Nakamura K, Kano H, Prado M, Kuwabara S. Fasciculation intensity and limb dominance in amyotrophic lateral sclerosis: a muscle ultrasonographic study. BMC Neurol 2022; 22:85. [PMID: 35277126 PMCID: PMC8915448 DOI: 10.1186/s12883-022-02617-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 03/07/2022] [Indexed: 11/10/2022] Open
Abstract
Background and purpose Muscle ultrasonography has been increasingly recognized as a useful tool for detection of fasciculations. Separately, concordance between dominant hand and onset side has been reported in amyotrophic lateral sclerosis (ALS). The aim of this study was to reveal the distribution of fasciculations in the whole body, focusing on handedness. Methods In 106 consecutive patients with ALS, muscle ultrasonography was systematically performed in 11 muscles (the tongue, and bilateral biceps brachii, 1st dorsal interosseous [FDI], T10-paraspinalis, vastus lateralis and tibialis anterior muscles). The fasciculation intensity was scored from 0 to 3 for each muscle. Results Fasciculations were more frequently found in the limb muscles than the tongue and paraspinalis. Side and handedness analyses revealed that fasciculation intensity in FDI was significantly more prominent on the right (median [inter-quartile range] 2 [0 - 3]) than left (1.5 [0 - 3]; p = 0.016), and in the dominant hand (2 [1 - 3]) than non-dominant side (1.5 [0 - 3]; p = 0.025). The differences were greater in patients with upper limb onset. There were no side differences in the lower limb muscles. Multivariate analyses showed that male patients had more frequent fasciculations in the dominant FDI (β = 0.22, p < 0.05). Conclusion More intensive fasciculations are present in the FDI in the dominant hand and gender might be associated with fasciculation intensities. This distribution pattern of fasciculations might be associated with pathogenesis of ALS.
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Neural basis for estrous cycle-dependent control of female behaviors. Neurosci Res 2021; 176:1-8. [PMID: 34331974 DOI: 10.1016/j.neures.2021.07.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/25/2021] [Accepted: 07/12/2021] [Indexed: 01/30/2023]
Abstract
Females display changes in distinct behaviors along the estrous cycle. Levels of circulating ovarian sex steroid hormones peak around ovulation, which occur around estrus phase of the cycle. This increase of sex hormones is thought to be important for changes in behaviors, however, neural circuit mechanisms of periodic behavioral changes in females are not understood well. Different lines of research indicate sex hormonal effects on several forms of neuronal plasticity. This review provides an overview of behavioral and plastic changes that occur in an estrous cycle-dependent manner and explores the current research linking these changes to understand neural circuit mechanisms that control female behaviors.
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17β-Estradiol Exacerbated Experimental Occlusal Interference-Induced Chronic Masseter Hyperalgesia by Increasing the Neuronal Excitability and TRPV1 Function of Trigeminal Ganglion in Ovariectomized Rats. Int J Mol Sci 2021; 22:ijms22136945. [PMID: 34203300 PMCID: PMC8269106 DOI: 10.3390/ijms22136945] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/14/2021] [Accepted: 06/20/2021] [Indexed: 12/17/2022] Open
Abstract
Pain symptoms in temporomandibular disorders (TMD) predominantly affect reproductive women, suggesting that estrogen regulates pain perception. However, how estrogen contributes to chronic TMD pain remains largely unclear. In the present study, we performed behavioral tests, electrophysiology, Western blot and immunofluorescence to investigate the role and underlying mechanisms of estrogen in dental experimental occlusal interference (EOI)-induced chronic masseter mechanical hyperalgesia in rats. We found that long-term 17β-estradiol (E2) replacement exacerbated EOI-induced masseter hyperalgesia in a dose-dependent manner in ovariectomized (OVX) rats. Whole-cell patch-clamp recordings demonstrated that E2 (100 nM) treatment enhanced the excitability of isolated trigeminal ganglion (TG) neurons in OVX and OVX EOI rats, and EOI increased the functional expression of transient receptor potential vanilloid-1 (TRPV1). In addition, E2 replacement upregulated the protein expression of TRPV1 in EOI-treated OVX rats. Importantly, intraganglionic administration of the TRPV1 antagonist AMG-9810 strongly attenuated the facilitatory effect of E2 on EOI-induced masseter mechanical sensitivity. These results demonstrate that E2 exacerbated EOI-induced chronic masseter mechanical hyperalgesia by increasing TG neuronal excitability and TRPV1 function. Our study helps to elucidate the E2 actions in chronic myogenic TMD pain and may provide new therapeutic targets for relieving estrogen-sensitive pain.
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Löhndorf A, Hosang L, Dohle W, Odoardi F, Waschkowski SA, Rosche A, Bauche A, Winzer R, Tolosa E, Windhorst S, Marry S, Flügel A, Potter BVL, Diercks BP, Guse AH. 2-Methoxyestradiol and its derivatives inhibit store-operated Ca 2+ entry in T cells: Identification of a new and potent inhibitor. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:118988. [PMID: 33581218 PMCID: PMC8062851 DOI: 10.1016/j.bbamcr.2021.118988] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 01/29/2021] [Accepted: 02/04/2021] [Indexed: 12/15/2022]
Abstract
T cell activation starts with formation of second messengers that release Ca2+ from the endoplasmic reticulum (ER) and thereby activate store-operated Ca2+ entry (SOCE), one of the essential signals for T cell activation. Recently, the steroidal 2-methoxyestradiol was shown to inhibit nuclear translocation of the nuclear factor of activated T cells (NFAT). We therefore investigated 2-methoxyestradiol for inhibition of Ca2+ entry in T cells, screened a library of 2-methoxyestradiol analogues, and characterized the derivative 2-ethyl-3-sulfamoyloxy-17β-cyanomethylestra-1,3,5(10)-triene (STX564) as a novel, potent and specific SOCE inhibitor. STX564 inhibits Ca2+ entry via SOCE without affecting other ion channels and pumps involved in Ca2+ signaling in T cells. Downstream effects such as cytokine expression and cell proliferation were also inhibited by both 2-methoxyestradiol and STX564, which has potential as a new chemical biology tool.
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Affiliation(s)
- Anke Löhndorf
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Leon Hosang
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Centre Göttingen, Von-Siebold-Straße 3a, D-37075 Göttingen, Germany
| | - Wolfgang Dohle
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Francesca Odoardi
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Centre Göttingen, Von-Siebold-Straße 3a, D-37075 Göttingen, Germany
| | - Sissy-Alina Waschkowski
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Anette Rosche
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Andreas Bauche
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Riekje Winzer
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Eva Tolosa
- Department of Immunology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Sabine Windhorst
- Department of Biochemistry and Signal Transduction, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Stephen Marry
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Centre Göttingen, Von-Siebold-Straße 3a, D-37075 Göttingen, Germany
| | - Alexander Flügel
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Centre Göttingen, Von-Siebold-Straße 3a, D-37075 Göttingen, Germany
| | - Barry V L Potter
- Drug Discovery & Medicinal Chemistry, Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
| | - Björn-Philipp Diercks
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany
| | - Andreas H Guse
- The Ca(2+) Signalling Group, Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, D-20246 Hamburg, Germany.
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Excitability Properties of Distal Motor Axons in the Human Ulnar Nerve. NEUROPHYSIOLOGY+ 2020. [DOI: 10.1007/s11062-020-09862-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Taxier LR, Gross KS, Frick KM. Oestradiol as a neuromodulator of learning and memory. Nat Rev Neurosci 2020; 21:535-550. [PMID: 32879508 DOI: 10.1038/s41583-020-0362-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/31/2020] [Indexed: 12/24/2022]
Abstract
Although hormones such as glucocorticoids have been broadly accepted in recent decades as general neuromodulators of memory processes, sex steroid hormones such as the potent oestrogen 17β-oestradiol have been less well recognized by the scientific community in this capacity. The predominance of females in studies of oestradiol and memory and the general (but erroneous) perception that oestrogens are 'female' hormones have probably prevented oestradiol from being more widely considered as a key memory modulator in both sexes. Indeed, although considerable evidence supports a crucial role for oestradiol in regulating learning and memory in females, a growing body of literature indicates a similar role in males. This Review discusses the mechanisms of oestradiol signalling and provides an overview of the effects of oestradiol on spatial, object recognition, social and fear memories. Although the primary focus is on data collected in females, effects of oestradiol on memory in males will be discussed, as will sex differences in the molecular mechanisms that regulate oestrogenic modulation of memory, which may have important implications for the development of future cognitive therapeutics.
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Affiliation(s)
- Lisa R Taxier
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Kellie S Gross
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, USA.
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10
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Fernández de Sevilla D, Núñez A, Buño W. Muscarinic Receptors, from Synaptic Plasticity to its Role in Network Activity. Neuroscience 2020; 456:60-70. [PMID: 32278062 DOI: 10.1016/j.neuroscience.2020.04.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 03/27/2020] [Accepted: 04/01/2020] [Indexed: 12/13/2022]
Abstract
Acetylcholine acting via metabotropic receptors plays a key role in learning and memory by regulating synaptic plasticity and circuit activity. However, a recent overall view of the effects of muscarinic acetylcholine receptors (mAChRs) on excitatory and inhibitory long-term synaptic plasticity and on circuit activity is lacking. This review focusses on specific aspects of the regulation of synaptic plasticity and circuit activity by mAChRs in the hippocampus and cortex. Acetylcholine increases the excitability of pyramidal neurons, facilitating the generation of dendritic Ca2+-spikes, NMDA-spikes and action potential bursts which provide the main source of Ca2+ influx necessary to induce synaptic plasticity. The activation of mAChRs induced Ca2+ release from intracellular IP3-sensitive stores is a major player in the induction of a NMDA independent long-term potentiation (LTP) caused by an increased expression of AMPA receptors in hippocampal pyramidal neuron dendritic spines. In the neocortex, activation of mAChRs also induces a long-term enhancement of excitatory postsynaptic currents. In addition to effects on excitatory synapses, a single brief activation of mAChRs together with short repeated membrane depolarization can induce a long-term enhancement of GABA A type (GABAA) inhibition through an increased expression of GABAA receptors in hippocampal pyramidal neurons. By contrast, a long term depression of GABAA inhibition (iLTD) is induced by muscarinic receptor activation in the absence of postsynaptic depolarizations. This iLTD is caused by an endocannabinoid-mediated presynaptic inhibition that reduces the GABA release probability at the terminals of inhibitory interneurons. This bidirectional long-term plasticity of inhibition may dynamically regulate the excitatory/inhibitory balance depending on the quiescent or active state of the postsynaptic pyramidal neurons. Therefore, acetylcholine can induce varied effects on neuronal activity and circuit behavior that can enhance sensory detection and processing through the modification of circuit activity leading to learning, memory and behavior.
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Affiliation(s)
- D Fernández de Sevilla
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029, Spain.
| | - A Núñez
- Departamento de Anatomía, Histología y Neurociencia, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid 28029, Spain
| | - W Buño
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid 28029, Spain
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Yousuf H, Smies CW, Hafenbreidel M, Tuscher JJ, Fortress AM, Frick KM, Mueller D. Infralimbic Estradiol Enhances Neuronal Excitability and Facilitates Extinction of Cocaine Seeking in Female Rats via a BDNF/TrkB Mechanism. Front Behav Neurosci 2019; 13:168. [PMID: 31417375 PMCID: PMC6684748 DOI: 10.3389/fnbeh.2019.00168] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Accepted: 07/11/2019] [Indexed: 11/13/2022] Open
Abstract
Women are more susceptible to developing cocaine dependence than men, but paradoxically, are more responsive to treatment. The potent estrogen, 17β-estradiol (E2), mediates these effects by augmenting cocaine seeking but also promoting extinction of cocaine seeking through E2's memory-enhancing functions. Although we have previously shown that E2 facilitates extinction, the neuroanatomical locus of action and underlying mechanisms are unknown. Here we demonstrate that E2 infused directly into the infralimbic-medial prefrontal cortex (IL-mPFC), a region critical for extinction consolidation, enhances extinction of cocaine seeking in ovariectomized (OVX) female rats. Using patch-clamp electrophysiology, we show that E2 may facilitate extinction by potentiating intrinsic excitability of IL-mPFC neurons. Because the mnemonic effects of E2 are known to be regulated by brain-derived neurotrophic factor (BDNF) and its receptor, tropomyosin-related kinase B (TrkB), we examined whether BDNF/TrkB signaling was necessary for E2-induced enhancement of excitability and extinction. We found that E2-mediated increases in excitability of IL-mPFC neurons were abolished by Trk receptor blockade. Moreover, blockade of TrkB signaling impaired E2-facilitated extinction of cocaine seeking in OVX female rats. Thus, E2 enhances IL-mPFC neuronal excitability in a TrkB-dependent manner to support extinction of cocaine seeking. Our findings suggest that pharmacological enhancement of E2 or BDNF/TrkB signaling during extinction-based therapies would improve therapeutic outcome in cocaine-addicted women.
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Affiliation(s)
- Hanna Yousuf
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Chad W Smies
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Madalyn Hafenbreidel
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Jennifer J Tuscher
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Ashley M Fortress
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States
| | - Devin Mueller
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI, United States.,Department of Biological Sciences, Kent State University, Kent, OH, United States
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12
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Modulation of neuronal activity in the Drosophila mushroom body by DopEcR, a unique dual receptor for ecdysone and dopamine. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1578-1588. [PMID: 28554773 DOI: 10.1016/j.bbamcr.2017.05.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 05/08/2017] [Accepted: 05/24/2017] [Indexed: 11/22/2022]
Abstract
G-protein-coupled receptors (GPCRs) for steroid hormones mediate unconventional steroid signaling and play a significant role in the rapid actions of steroids in a variety of biological processes, including those in the nervous system. However, the effects of these GPCRs on overall neuronal activity remain largely elusive. Drosophila DopEcR is a GPCR that responds to both ecdysone (the major steroid hormone in insects) and dopamine, regulating multiple second messenger systems. Recent studies have revealed that DopEcR is preferentially expressed in the nervous system and involved in behavioral regulation. Here we utilized the bioluminescent Ca2+-indicator GFP-aequorin to monitor the nicotine-induced Ca2+-response within the mushroom bodies (MB), a higher-order brain center in flies, and examined how DopEcR modulates these Ca2+-dynamics. Our results show that in DopEcR knockdown flies, the nicotine-induced Ca2+-response in the MB was significantly enhanced selectively in the medial lobes. We then reveal that application of DopEcR's ligands, ecdysone and dopamine, had different effects on nicotine-induced Ca2+-responses in the MB: ecdysone enhanced activity in the calyx and cell body region in a DopEcR-dependent manner, whereas dopamine reduced activity in the medial lobes independently of DopEcR. Finally, we show that flies with reduced DopEcR function in the MB display decreased locomotor activity. This behavioral phenotype of DopEcR-deficient flies may be partly due to their enhanced MB activity, since the MB have been implicated in the suppression of locomotor activity. Overall, these data suggest that DopEcR is involved in region-specific modulation of Ca2+ dynamics within the MB, which may play a role in behavioral modulation.
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13
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Kow LM, Pfaff DW. Rapid estrogen actions on ion channels: A survey in search for mechanisms. Steroids 2016; 111:46-53. [PMID: 26939826 PMCID: PMC4929851 DOI: 10.1016/j.steroids.2016.02.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 02/22/2016] [Accepted: 02/25/2016] [Indexed: 12/31/2022]
Abstract
A survey of nearly two hundred reports shows that rapid estrogenic actions can be detected across a range of kinds of estrogens, a range of doses, on a wide range of tissue, cell and ion channel types. Striking is the fact that preparations of estrogenic agents that do not permeate the cell membrane almost always mimic the actions of the estrogenic agents that do permeate the membrane. All kinds of estrogens, ranging from natural ones, through receptor modulators, endocrine disruptors, phytoestrogens, agonists, and antagonists to novel G-1 and STX, have been reported to be effective. For actions on specific types of ion channels, the possibility of opposing actions, in different cases, is the rule, not the exception. With this variety there is no single, specific action mechanism for estrogens per se, although in some cases estrogens can act directly or via some signaling pathways to affect ion channels. We infer that estrogens can bind a large number of substrates/receptors at the membrane surface. As against the variety of subsequent routes of action, this initial step of the estrogen's binding action is the key.
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Affiliation(s)
- Lee-Ming Kow
- The Rockefeller University, New York, NY 10065, USA.
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14
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Lai YJ, Yu D, Zhang JH, Chen GJ. Cooperation of Genomic and Rapid Nongenomic Actions of Estrogens in Synaptic Plasticity. Mol Neurobiol 2016; 54:4113-4126. [PMID: 27324789 PMCID: PMC5509832 DOI: 10.1007/s12035-016-9979-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/14/2016] [Indexed: 12/23/2022]
Abstract
Neuroplasticity refers to the changes in the molecular and cellular processes of neural circuits that occur in response to environmental experiences. Clinical and experimental studies have increasingly shown that estrogens participate in the neuroplasticity involved in cognition, behavior, and memory. It is generally accepted that estrogens exert their effects through genomic actions that occur over a period of hours to days. However, emerging evidence indicates that estrogens also rapidly influence the neural circuitry through nongenomic actions. In this review, we provide an overview of the genomic and nongenomic actions of estrogens and discuss how these actions may cooperate in synaptic plasticity. We then summarize the role of epigenetic modifications, synaptic protein synthesis, and posttranslational modifications, and the splice variants of estrogen receptors in the complicated network of estrogens. The combination of genomic and nongenomic mechanisms endows estrogens with considerable diversity in modulating neural functions including synaptic plasticity.
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Affiliation(s)
- Yu-Jie Lai
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - Dan Yu
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - John H Zhang
- Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Guo-Jun Chen
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China.
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15
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Sato SM, Woolley CS. Acute inhibition of neurosteroid estrogen synthesis suppresses status epilepticus in an animal model. eLife 2016; 5. [PMID: 27083045 PMCID: PMC4862752 DOI: 10.7554/elife.12917] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Accepted: 04/11/2016] [Indexed: 12/31/2022] Open
Abstract
Status epilepticus (SE) is a common neurological emergency for which new treatments are needed. In vitro studies suggest a novel approach to controlling seizures in SE: acute inhibition of estrogen synthesis in the brain. Here, we show in rats that systemic administration of an aromatase (estrogen synthase) inhibitor after seizure onset strongly suppresses both electrographic and behavioral seizures induced by kainic acid (KA). We found that KA-induced SE stimulates synthesis of estradiol (E2) in the hippocampus, a brain region commonly involved in seizures and where E2 is known to acutely promote neural activity. Hippocampal E2 levels were higher in rats experiencing more severe seizures. Consistent with a seizure-promoting effect of hippocampal estrogen synthesis, intra-hippocampal aromatase inhibition also suppressed seizures. These results reveal neurosteroid estrogen synthesis as a previously unknown factor in the escalation of seizures and suggest that acute administration of aromatase inhibitors may be an effective treatment for SE. DOI:http://dx.doi.org/10.7554/eLife.12917.001 Seizures occur when connected groups of cells in the brain become over-active and fire together. Current anti-seizure medications work by reducing brain activity generally. Although this is often effective in controlling seizures, it can also lead to negative side effects like drowsiness, dizziness or difficulty concentrating. A better alternative would be to target a factor that promotes activity especially during seizures. Most people think of estrogens as being female sex hormones. However, estrogens are also made in the brain of both sexes, where they could promote activity during seizures. Sato and Woolley therefore set out to test a two-part hypothesis: that seizures stimulate the production of estrogen in the brain, and that inhibiting this production process just as seizures begin would make seizures less severe. Sato and Woolley studied male and female rats and found that in both sexes, seizures stimulate the production of estrogens in the hippocampus – a part of the brain that is often involved in seizures. Because estrogens are known to increase the activity of cells in the hippocampus, this suggested that estrogens that are produced in the brain during seizures could make seizures worse. Sato and Woolley tested this by injecting rats with a drug that inhibits estrogen production, called an aromatase inhibitor, shortly after seizures began. The drug strongly suppressed seizures, whereas control rats that did not receive the injection continued to have seizures. Overall, Sato and Woolley show that the production of estrogen in the brain escalates seizure activity, and suggest that aromatase inhibitors may be useful for controlling seizures. Several questions remain that require further study. How does seizure activity lead to estrogen being made in the brain? How do estrogen levels go back down after a seizure? What circumstances other than seizures stimulate brain estrogen production, and what roles does this production process play in activity that is not related to seizures? DOI:http://dx.doi.org/10.7554/eLife.12917.002
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Affiliation(s)
- Satoru M Sato
- Department of Neurobiology, Northwestern University, Evanston, United States
| | - Catherine S Woolley
- Department of Neurobiology, Northwestern University, Evanston, United States
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16
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Underwood EL, Thompson LT. High-fat diet impairs spatial memory and hippocampal intrinsic excitability and sex-dependently alters circulating insulin and hippocampal insulin sensitivity. Biol Sex Differ 2016; 7:9. [PMID: 26823968 PMCID: PMC4730722 DOI: 10.1186/s13293-016-0060-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 01/18/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND High-fat diets promoting obesity/type-2 diabetes can impair physiology and cognitive performance, although sex-dependent comparisons of these impairments are rarely made. Transient reductions in Ca(2+)-dependent afterhyperpolarizations (AHPs) occur during memory consolidation, enhancing intrinsic excitability of hippocampal CA1 pyramidal neurons. In rats fed standard diets, insulin can enhance memory and reduce amplitude and duration of AHPs. METHODS Effects of chronic high-fat diet (HFD) on memory, circulating insulin, and neuronal physiology were compared between young adult male and female Long-Evans rats. Rats fed for 12 weeks (from weaning) a HFD or a control diet (CD) were then tested in vivo prior to in vitro recordings from CA1 pyramidal neurons. RESULTS The HFD significantly impaired spatial memory in both males and females. Significant sex differences occurred in circulating insulin and in the insulin sensitivity of hippocampal neurons. Circulating insulin significantly increased in HFD males but decreased in HFD females. While the HFD significantly reduced hippocampal intrinsic excitability in both sexes, CA1 neurons from HFD females remained insulin-sensitive but those from HFD males became insulin-insensitive. CONCLUSIONS Findings consistent with these have been characterized previously in HFD or senescent males, but the effects observed here in young females are unique. Loss of CA1 neuronal excitability, and sex-dependent loss of insulin sensitivity, can have significant cognitive consequences, over both the short term and the life span. These findings highlight needs for more research into sex-dependent differences, relating systemic and neural plasticity mechanisms in metabolic disorders.
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Affiliation(s)
- Erica L. Underwood
- Cognition & Neuroscience Program, School of Behavioral & Brain Sciences, University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080 USA
| | - Lucien T. Thompson
- Cognition & Neuroscience Program, School of Behavioral & Brain Sciences, University of Texas at Dallas, 800 W. Campbell Rd., Richardson, TX 75080 USA
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17
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Frick KM, Kim J, Tuscher JJ, Fortress AM. Sex steroid hormones matter for learning and memory: estrogenic regulation of hippocampal function in male and female rodents. Learn Mem 2015; 22:472-93. [PMID: 26286657 PMCID: PMC4561402 DOI: 10.1101/lm.037267.114] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 07/09/2015] [Indexed: 01/24/2023]
Abstract
Ample evidence has demonstrated that sex steroid hormones, such as the potent estrogen 17β-estradiol (E2), affect hippocampal morphology, plasticity, and memory in male and female rodents. Yet relatively few investigators who work with male subjects consider the effects of these hormones on learning and memory. This review describes the effects of E2 on hippocampal spinogenesis, neurogenesis, physiology, and memory, with particular attention paid to the effects of E2 in male rodents. The estrogen receptors, cell-signaling pathways, and epigenetic processes necessary for E2 to enhance memory in female rodents are also discussed in detail. Finally, practical considerations for working with female rodents are described for those investigators thinking of adding females to their experimental designs.
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Affiliation(s)
- Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Jaekyoon Kim
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Jennifer J Tuscher
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
| | - Ashley M Fortress
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53211, USA
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18
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Frick KM. Molecular mechanisms underlying the memory-enhancing effects of estradiol. Horm Behav 2015; 74:4-18. [PMID: 25960081 PMCID: PMC4573242 DOI: 10.1016/j.yhbeh.2015.05.001] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Revised: 04/25/2015] [Accepted: 05/01/2015] [Indexed: 11/18/2022]
Abstract
This article is part of a Special Issue "Estradiol and cognition". Since the publication of the 1998 special issue of Hormones and Behavior on estrogens and cognition, substantial progress has been made towards understanding the molecular mechanisms through which 17β-estradiol (E2) regulates hippocampal plasticity and memory. Recent research has demonstrated that rapid effects of E2 on hippocampal cell signaling, epigenetic processes, and local protein synthesis are necessary for E2 to facilitate the consolidation of object recognition and spatial memories in ovariectomized female rodents. These effects appear to be mediated by non-classical actions of the intracellular estrogen receptors ERα and ERβ, and possibly by membrane-bound ERs such as the G-protein-coupled estrogen receptor (GPER). New findings also suggest a key role of hippocampally-synthesized E2 in regulating hippocampal memory formation. The present review discusses these findings in detail and suggests avenues for future study.
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Affiliation(s)
- Karyn M Frick
- Department of Psychology, University of Wisconsin-Milwaukee, 2441 E. Hartford Ave., Milwaukee, WI 53211, USA.
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19
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Saleeon W, Jansri U, Srikiatkhachorn A, Bongsebandhu-Phubhakdi S. The estrous cycle modulates voltage-gated ion channels in trigeminal ganglion neurons. J Physiol Sci 2015; 65:S29-S35. [PMID: 31941171 PMCID: PMC10722641 DOI: 10.1007/bf03405853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Migraines typically occur more frequently in women than men because of the effects of estrogen on both the frequency and severity of migraine attacks. Many women suffer from migraine attacks during menstruation, which are known as menstrual migraines. The pathophysiology of menstrual migraines can be explored by using the rat estrous cycle, which shows a cyclical fluctuation of estrogen level that resembles the menstrual cycle. The aim of this study was to investigate whether different stages of the estrous cycle are involved in migraine development by comparing the excitability of trigeminal ganglion (TG) neurons in four different stages of the estrous cycle by using action potential (AP) parameter assessments. The stages of the estrous cycle were identified by a vaginal smear and measuring the estrogen levels in collected blood. The proestrus and estrus stages had higher estrogen levels compared with the diestrus and metestrus stages. Whole-cell patch clamp recordings demonstrated that TG neurons in the proestrus and estrus stage had lower AP threshold, lower rheobase, higher AP height, shorter AP falling time and deeper afterhyperpolarization (AHP) depth. Hence, our results revealed that the high level of estrogen in the proestrus and estrus stage alters the AP properties of TG neurons. Estrogen may increase membrane excitability and the summation of cellular responses, which alters the AP properties. The alterations of the AP properties in the proestrus and estrus stage may relate to a modification of voltage-gated ion channels in TG neurons, which is a pathogenesis for menstrual migraine. No COI.
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Affiliation(s)
- Wachirapong Saleeon
- Department of Physiology, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand
| | - Ukkrit Jansri
- Research Affairs, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand
| | - Anan Srikiatkhachorn
- Department of Physiology, Faculty of Medicine, Chulalongkorn University, 1873 Rama IV Road, Pathumwan, Bangkok, Thailand
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20
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Activation of GPR30 attenuates chronic pain-related anxiety in ovariectomized mice. Psychoneuroendocrinology 2015; 53:94-107. [PMID: 25614360 DOI: 10.1016/j.psyneuen.2014.12.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 12/24/2014] [Accepted: 12/29/2014] [Indexed: 11/21/2022]
Abstract
Estrogen regulates neuroendocrine and inflammatory processes that play critical roles in neuroinflammation, anxiety, and chronic pain. Patients suffering from chronic pain often complain of anxiety. However, limited information is available regarding the neural circuitry of chronic pain-related anxiety and the related function of estrogen. Hindpaw injection of complete Freund's adjuvant (CFA) and chronic constriction injury (CCI) of the sciatic nerve induced notable pain sensitization and anxiety-like behavior in ovariectomized (OVX) mice. We found that the level of G-protein-coupled receptor 30 (GPR30), a membrane estrogen receptor, was significantly increased in the basolateral amygdala (BLA) of ovariectomized (OVX) mice suffering from chronic inflammatory and neuropathic pain. Subcutaneous injection or BLA local infusion of the GPR30 agonist G1 significantly reduced anxiety-like behavior in CFA-injected and CCI-OVX mice; however, this treatment did not alter the nociceptive threshold. GPR30 knock down by shRNA in the BLA of OVX mice inhibited the anxiolytic effects of GPR30 activation. G1 administration reversed the upregulation of GluR1 subunit in AMPA and NR2A-containing NMDA receptors and the downregulation of GABAA receptors in the BLA of CFA-injected and CCI-OVX mice. Electrophysiological recording revealed that GPR30 activation could prevent imbalance between excitatory and inhibitory transmissions in the BLA synapses of CFA-injected OVX mice. In conclusion, GPR30 activation induced anxiolytic effects but did not affect the nociceptive threshold of mice under chronic pain. The anxiolytic effects of GPR30 were partially due to maintaining the balance between excitatory and inhibitory transmissions in the BLA.
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21
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Segarra AC, Torres-Díaz YM, Silva RD, Puig-Ramos A, Menéndez-Delmestre R, Rivera-Bermúdez JG, Amadeo W, Agosto-Rivera JL. Estrogen receptors mediate estradiol's effect on sensitization and CPP to cocaine in female rats: role of contextual cues. Horm Behav 2014; 65:77-87. [PMID: 24355096 PMCID: PMC3963412 DOI: 10.1016/j.yhbeh.2013.12.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 12/06/2013] [Accepted: 12/10/2013] [Indexed: 10/25/2022]
Abstract
Preclinical studies show that estradiol enhances sensitization to cocaine in females by mechanisms not fully understood. These studies consistently show that ovariectomized (OVX) rats exhibit little or no sensitization to cocaine compared to OVX rats administered estradiol. In this study we varied the dose of cocaine (10, 15, and 30mg/kg), the length of cocaine treatment (from 5 to 10days) and the context of cocaine injections to determine if these factors play a role on estradiol's effects on cocaine sensitization. Because OVX rats are hormonally compromised, they are not representative of the natural state of the animal, and thus the physiological context of these studies remains unclear. To address this issue, we blocked ERs in gonadally intact females by icv administration of the antiestrogen ICI-182,780. Varying the dose or length of exposure to cocaine does not alter estradiol's effect on cocaine sensitization. In contrast, a highly context-dependent sensitization protocol results in robust sensitization even in OVX rats. Interestingly, using this protocol, sensitization in OVX rats diminished with time, suggesting that estradiol is necessary for the maintenance of cocaine sensitization. Blocking brain ERs with ICI completely abolishes the development and expression of cocaine sensitization in gonadally intact female rats, even when tested in a highly context-dependent sensitization protocol. Given these findings, we propose that activation of brain ERs is required for the development and maintenance of sensitization and CPP.
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Affiliation(s)
- Annabell C Segarra
- University of Puerto Rico, Physiology Department, Medical Sciences Campus, P.O. Box 365067, San Juan 00936-5067, Puerto Rico.
| | - Yvonne M Torres-Díaz
- University of Puerto Rico, Physiology Department, Medical Sciences Campus, P.O. Box 365067, San Juan 00936-5067, Puerto Rico
| | - Richard D Silva
- Biology Department, Rio Piedras Campus, P.O. Box 23360, San Juan 00931, Puerto Rico
| | - Anabel Puig-Ramos
- University of Puerto Rico, Physiology Department, Medical Sciences Campus, P.O. Box 365067, San Juan 00936-5067, Puerto Rico
| | - Raissa Menéndez-Delmestre
- University of Puerto Rico, Physiology Department, Medical Sciences Campus, P.O. Box 365067, San Juan 00936-5067, Puerto Rico
| | | | - Waldo Amadeo
- University of Puerto Rico, Physiology Department, Medical Sciences Campus, P.O. Box 365067, San Juan 00936-5067, Puerto Rico
| | - José L Agosto-Rivera
- Biology Department, Rio Piedras Campus, P.O. Box 23360, San Juan 00931, Puerto Rico
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22
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Hao X, Li X, Li X. 17β-estradiol downregulated the expression of TASK-1 channels in mouse neuroblastoma N2A cells. J Membr Biol 2014; 247:273-9. [PMID: 24435466 DOI: 10.1007/s00232-014-9632-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/06/2014] [Indexed: 01/23/2023]
Abstract
TASK channels, an acid-sensitive subgroup of two pore domain K⁺ (K2P) channels family, were widely expressed in a variety of neural tissues, and exhibited potent functions such as the regulation of membrane potential. The steroid hormone estrogen was able to interact with K⁺ channels, including voltage-gated K⁺ (Kv) and large conductance Ca²⁺-activated (BK) K⁺ channels, in different types of cells like cardiac myocytes and neurons. However, it is unclear about the effects of estrogen on TASK channels. In the present study, the expressions of two members of acid-sensitive TASK channels, TASK-1 and TASK-2, were detected in mouse neuroblastoma N2A cells by RT-PCR. Extracellular acidification (pH 6.4) weakly but statistically significantly inhibited the outward background current by 22.9 % at a holding potential of 0 mV, which inactive voltage-gated K⁺ currents, suggesting that there existed the functional TASK channels in the membrane of N2A cells. Although these currents were not altered by the acute application of 100 nM 17β-estradiol, incubation with 10 nM 17β-estradiol for 48 h reduced the mRNA level of TASK-1 channels by 40.4 % without any effect on TASK-2 channels. The proliferation rates of N2A cells were also increased by treatment with 10 nM 17β-estradiol for 48 h. These data implied that N2A cells expressed functional TASK channels and chronic exposure to 17β-estradiol downregulated the expression of TASK-1 channels and improved cell proliferation. The effect of 17β-estradiol on TASK-1 channels might be an alternative mechanism for the neuroprotective action of 17β-estradiol.
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Affiliation(s)
- Xuran Hao
- Department of Biomedical Engineering, South-Central University for Nationalities, 182 Minyuan Road, Wuhan, 430074, China
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23
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Park S, Nozaki K, Smith JA, Krause JS, Banik NL. Cross-talk between IGF-1 and estrogen receptors attenuates intracellular changes in ventral spinal cord 4.1 motoneuron cells because of interferon-gamma exposure. J Neurochem 2013; 128:904-18. [PMID: 24188094 DOI: 10.1111/jnc.12520] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 10/16/2013] [Accepted: 10/21/2013] [Indexed: 12/26/2022]
Abstract
Insulin-like growth factor-1 (IGF-1) is a neuroprotective growth factor that promotes neuronal survival by inhibition of apoptosis. To examine whether IGF-1 exerts cytoprotective effects against extracellular inflammatory stimulation, ventral spinal cord 4.1 (VSC4.1) motoneuron cells were treated with interferon-gamma (IFN-γ). Our data demonstrated apoptotic changes, increased calpain:calpastatin and Bax:Bcl-2 ratios, and expression of apoptosis-related proteases (caspase-3 and -12) in motoneurons rendered by IFN-γ in a dose-dependent manner. Post-treatment with IGF-1 attenuated these changes. In addition, IGF-1 treatment of motoneurons exposed to IFN-γ decreased expression of inflammatory markers (cyclooxygenase-2 and nuclear factor-kappa B:inhibitor of kappa B ratio). Furthermore, IGF-1 attenuated the loss of expression of IGF-1 receptors (IGF-1Rα and IGF-1Rβ) and estrogen receptors (ERα and ERβ) induced by IFN-γ. To determine whether the protective effects of IGF-1 are associated with ERs, ERs antagonist ICI and selective siRNA targeted against ERα and ERβ were used in VSC4.1 motoneurons. Distinctive morphological changes were observed following siRNA knockdown of ERα and ERβ. In particular, apoptotic cell death assessed by TUNEL assay was enhanced in both ERα and ERβ-silenced VSC4.1 motoneurons following IFN-γ and IGF-1 exposure. These results suggest that IGF-1 protects motoneurons from inflammatory insult by a mechanism involving pivotal interactions with ERα and ERβ.
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Affiliation(s)
- Sookyoung Park
- Department of Neurosciences, Division of Neurology, College of Health Professions, Medical University of South Carolina, Charleston, South Carolina, USA
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24
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Babayan AH, Kramár EA. Rapid effects of oestrogen on synaptic plasticity: interactions with actin and its signalling proteins. J Neuroendocrinol 2013; 25:1163-72. [PMID: 24112361 PMCID: PMC3989941 DOI: 10.1111/jne.12108] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 09/09/2013] [Accepted: 09/16/2013] [Indexed: 01/02/2023]
Abstract
Oestrogen rapidly enhances fast excitatory postsynaptic potentials, facilitates long-term potentiation (LTP) and increases spine numbers. Each effect likely contributes to the influence of the steroid on cognition and memory. In the present review, we first describe a model for the substrates of LTP that includes an outline of the synaptic events occurring during induction, expression and consolidation. Briefly, critical signalling pathways involving the small GTPases RhoA and Rac/Cdc42 are activated by theta burst-induced calcium influx and initiate actin filament assembly via phosphorylation (inactivation) of cofilin. Reorganisation of the actin cytoskeleton changes spine and synapse morphology, resulting in increased concentrations of AMPA receptors at stimulated contacts. We then use the synaptic model to develop a specific hypothesis about how oestrogen affects both baseline transmission and plasticity. Brief infusions of 17β-oestradiol (E2 ) reversibly stimulate the RhoA, cofilin phosphorylation and actin polymerisation cascade of the LTP machinery; blocking this eliminates the effects of the steroid on transmission. We accordingly propose that E2 induces a weak form of LTP and thereby increases synaptic responses, a hypothesis that also accounts for how it markedly enhances theta burst induced potentiation. Although the effects of E2 on the cytoskeleton could be a result of the direct activation of small GTPases by oestrogen receptors on the synaptic membrane, the hormone also activates tropomyosin-related kinase B receptors for brain-derived neurotrophic factor, a neurotrophin that engages the RhoA-cofilin sequence and promotes LTP. The latter observations raise the possibility that E2 produces its effects on synaptic physiology via transactivation of neighbouring receptors that have prominent roles in the management of spine actin, synaptic physiology and plasticity.
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Affiliation(s)
- A H Babayan
- Department of Anatomy and Neurobiology, University of California, Irvine, CA, USA
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25
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Frick KM. Epigenetics, oestradiol and hippocampal memory consolidation. J Neuroendocrinol 2013; 25:1151-62. [PMID: 24028406 PMCID: PMC3943552 DOI: 10.1111/jne.12106] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 08/13/2013] [Accepted: 09/05/2013] [Indexed: 02/02/2023]
Abstract
Epigenetic alterations of histone proteins and DNA are essential for hippocampal synaptic plasticity and cognitive function, and contribute to the aetiology of psychiatric disorders and neurodegenerative diseases. Hippocampal memory formation depends on histone alterations and DNA methylation, and increasing evidence suggests that the regulation of these epigenetic processes by modulatory factors, such as environmental enrichment, stress and hormones, substantially influences memory function. Recent work from our laboratory suggests that the ability of the sex-steroid hormone 17β-oestradiol (E2 ) to enhance novel object recognition memory consolidation in young adult female mice is dependent on histone H3 acetylation and DNA methylation in the dorsal hippocampus. Our data also suggest that enzymes mediating DNA methylation and histone acetylation work in concert to regulate the effects of E2 on memory consolidation. These findings shed light on the epigenetic mechanisms that influence hormonal modulation of cognitive function, and may have important implications for understanding how hormones influence cognition in adulthood and ageing. The present review provides a brief overview of the literature on epigenetics and memory, describes in detail our findings demonstrating that epigenetic alterations regulate E2 -induced memory enhancement in female mice, and discusses future directions for research on the epigenetic regulation of E2 -induced memory enhancement.
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Affiliation(s)
- Karyn M. Frick
- Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53211
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26
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Wilmott LA, Thompson LT. Sex- and dose-dependent effects of post-trial calcium channel blockade by magnesium chloride on memory for inhibitory avoidance conditioning. Behav Brain Res 2013; 257:49-53. [PMID: 24095881 DOI: 10.1016/j.bbr.2013.09.047] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/27/2013] [Accepted: 09/29/2013] [Indexed: 11/28/2022]
Abstract
Calcium influx through voltage-dependent Ca(2+) channels is critical for many neuronal processes required for learning and memory. Persistent increases in cytosolic intracellular Ca(2+) concentrations in aging neurons are associated with learning impairments, while small transient subcellular changes in intracellular calcium concentrations play critical roles in neural plasticity in young neurons. In the present study, young male and female Fisher 344 × Brown Norway (FBN) hybrid rats were administered different doses of magnesium chloride (0.0, 100.0, or 200.0mg/kg, i.p.) following a single inhibitory avoidance training trial. Extracellular magnesium ions can non-specifically block voltage-gated calcium channels, and/or reduce the calcium conductance gated via glutamate and serine's activation of neuronal NMDA receptors. In our study, magnesium chloride dose-dependently enhanced memory compared to controls (significantly increased latency to enter a dark compartment previously paired with an aversive stimulus) when tested 48 h later as compared to controls. A leftward shift in the dose response curve for memory enhancement by magnesium chloride was observed for male compared to female rats. These findings provide further insights into calcium-dependent modulation of aversive memory, and should be considered when assessing the design of effective treatment options for both male and female patients with dementia or other memory problems.
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Affiliation(s)
- Lynda A Wilmott
- The University of Texas at Dallas, Cognition & Neuroscience Program, School of Behavioral & Brain Sciences, 800 West Campbell Road, GR4.1, Richardson, TX 75080, USA
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Tian Z, Wang Y, Zhang N, Guo YY, Feng B, Liu SB, Zhao MG. Estrogen receptor GPR30 exerts anxiolytic effects by maintaining the balance between GABAergic and glutamatergic transmission in the basolateral amygdala of ovariectomized mice after stress. Psychoneuroendocrinology 2013; 38:2218-33. [PMID: 23669322 DOI: 10.1016/j.psyneuen.2013.04.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 04/09/2013] [Accepted: 04/10/2013] [Indexed: 11/25/2022]
Abstract
G-protein-coupled receptor 30 (GPR30)/G-protein-coupled estrogen receptor is a novel estrogen membrane receptor that localizes to the cell membrane and endoplasmic reticulum. GPR30 is widely distributed and has numerous physiological functions in the central nervous system. We found that GPR30 is highly expressed in the basolateral amygdala (BLA). Additionally, GPR30 expression in the amygdala of ovariectomized (OVX) mice significantly increased after acute stress and was accompanied by anxiety-like behaviors. These effects, however, were reversed by local infusion of the GPR30 agonist (G1) in the BLA. Protein assessments revealed that G1 attenuated the up-regulation of the GluR1 subunit of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor and NR2A-containing N-methyl-d-aspartate receptors (NMDARs) in the BLA of OVX mice using an acute stress paradigm. In the same model, we found that the agonist also blocked the down-regulation of γ-aminobutyric acid A (GABAA) receptors and NR2B-containing NMDARs. Electrophysiological recording showed that the activation of GPR30 increased the inhibitory synaptic transmission in the BLA. Overall, our results indicate that estradiol reduces anxiety-like behaviors induced by acute stress at least partially through GPR30 signaling, maintaining the balance between GABAergic and glutamatergic transmission in the BLA of OVX-stressed mice.
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Affiliation(s)
- Zhen Tian
- Department of Pharmacology, School of Pharmacy, The Fourth Military Medical University, Xi'an 710032, China
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Kelly MJ, Rønnekleiv OK. A selective membrane estrogen receptor agonist maintains autonomic functions in hypoestrogenic states. Brain Res 2013; 1514:75-82. [PMID: 23535448 PMCID: PMC5432040 DOI: 10.1016/j.brainres.2013.03.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 03/09/2013] [Accepted: 03/19/2013] [Indexed: 12/14/2022]
Abstract
It is well known that many of the actions of estrogens in the central nervous system are mediated via intracellular receptor/transcription factors that interact with steroid response elements on target genes. But there is also a compelling evidence for the involvement of membrane estrogen receptors in hypothalamic and other CNS functions. However, it is not well understood how estrogens signal via membrane receptors, and how these signals impact not only membrane excitability but also gene transcription in neurons. Indeed, it has been known for sometime that estrogens can rapidly alter neuronal activity within seconds, indicating that some cellular effects can occur via membrane delimited events. In addition, estrogens can affect second messenger systems including calcium mobilization and a plethora of kinases within neurons to alter cellular functions. Therefore, this brief review will summarize our current understanding of rapid membrane-initiated and intracellular signaling by estrogens in the hypothalamus, the nature of receptors involved and how these receptors contribute to maintenance of homeostatic functions, many of which go awry in menopausal states. This article is part of a Special Issue entitled Hormone Therapy.
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Affiliation(s)
- Martin J Kelly
- Department of Physiology and Pharmacology, L334, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098, USA.
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29
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Kelly MJ, Rønnekleiv OK. Membrane-initiated actions of estradiol that regulate reproduction, energy balance and body temperature. Front Neuroendocrinol 2012; 33:376-87. [PMID: 22871514 PMCID: PMC3618441 DOI: 10.1016/j.yfrne.2012.07.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 07/07/2012] [Accepted: 07/11/2012] [Indexed: 12/21/2022]
Abstract
It is well known that many of the actions of estrogens in the central nervous system are mediated via intracellular receptor/transcription factors that interact with steroid response elements on target genes. However, there now exists compelling evidence for membrane estrogen receptors in hypothalamic and other brain neurons. But, it is not well understood how estrogens signal via membrane receptors, and how these signals impact not only membrane excitability but also gene transcription in neurons. Indeed, it has been known for sometime that estrogens can rapidly alter neuronal activity within seconds, indicating that some cellular effects can occur via membrane delimited events. In addition, estrogens can affect second messenger systems including calcium mobilization and a plethora of kinases to alter cell signaling. Therefore, this review will consider our current knowledge of rapid membrane-initiated and intracellular signaling by estrogens in the hypothalamus, the nature of receptors involved and how they contribute to homeostatic functions.
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Affiliation(s)
- Martin J. Kelly
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239
- Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Oline K. Rønnekleiv
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR 97239
- Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
- Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University, Portland, OR 97239
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Li X, Zheng S, Dong X, Xiao J. 17β-Estradiol inhibits outward voltage-gated K⁺ currents in human osteoblast-like MG63 cells. J Membr Biol 2012; 246:39-45. [PMID: 22976040 DOI: 10.1007/s00232-012-9502-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 08/29/2012] [Indexed: 11/29/2022]
Abstract
Previous studies have shown that 17β-estradiol has a pivotal function by blocking voltage-gated K⁺ (Kv) channels in several different types of cells such as cardiac myocytes and neurons. Outward Kv currents can also be measured in osteoblasts, although little is known about the effects of 17β-estradiol on these currents. In human osteoblast-like MG63 cells, we found that 17β-estradiol inhibits peak and end Kv currents, with IC₅₀ values of 480 and 325 nM, respectively. To elucidate the mechanism of inhibition, the kinetics of Kv currents were investigated. The half-maximum activation potential (V(½)) was 1.3 mV and was shifted left to -4.4 mV after application of 500 nM 17β-estradiol. For steady-state inactivation, the V(½) was -55.0 mV and weakly shifted left to -58.2 mV. To identify the molecular basis of outward Kv currents in MG63 cells, we performed RT-PCR analyses. The expression of Kv2.1 channels appeared to dominate over that of other Kv channels in MG63 cells. In COS-7 cells with heterologously expressed Kv2.1 channels, 17β-estradiol also inhibits macroscopic currents of Kv2.1. Our data indicate that 17β-estradiol inhibits Kv currents in human osteoblast-like MG63 cells and that Kv2.1 is a potential molecular correlate of outward Kv currents in these cells.
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Affiliation(s)
- Xiantao Li
- College of Biomedical Engineering, South-Central University for Nationalities, 708 Minyuan Road, Wuhan 430074, People's Republic of China
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31
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Liu SB, Han J, Zhang N, Tian Z, Li XB, Zhao MG. Neuroprotective effects of oestrogen against oxidative toxicity through activation of G-protein-coupled receptor 30 receptor. Clin Exp Pharmacol Physiol 2011; 38:577-85. [DOI: 10.1111/j.1440-1681.2011.05549.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Kainate receptors with a metabotropic signature enhance hippocampal excitability by regulating the slow after-hyperpolarization in CA3 pyramidal neurons. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011. [PMID: 21713667 DOI: 10.1007/978-1-4419-9557-5_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Most of our knowledge of the synaptic function of kainate receptors stems from a detailed analysis of synaptic transmission between dentate granule cells and CA3 pyramidal neurons, where kainate receptors mediate a slow excitatory current with integrative properties ideally suited for repetitive neuronal firing. Besides this well characterized ionotropic effect of kainate receptors, they can also enhance neuronal excitability by inhibiting the slow Ca(2+) activated K(+) current I(sAHP) via a G-protein coupled mechanism. This phenomenon is associated with Ca(2+) mobilization and protein-kinase activation and ultimately leads to modulation of ion channels responsible for intrinsic electrical properties such as firing adaptation. The significance for CNS function of these newly emerging metabotropic kainate receptors is poorly understood and as yet proteomic analysis of kainate receptors has yielded little information on signaling molecules associated with the kainate receptor ionophore. This chapter covers the key findings that have led to the proposal that high-affinity postsynaptic kainate receptors trigger a form of metabotropic signaling regulating I(sAH P) and neuronal firing in CA3 hippocampal neurons.
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Druzin M, Malinina E, Grimsholm O, Johansson S. Mechanism of estradiol-induced block of voltage-gated K+ currents in rat medial preoptic neurons. PLoS One 2011; 6:e20213. [PMID: 21625454 PMCID: PMC3098870 DOI: 10.1371/journal.pone.0020213] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Accepted: 04/15/2011] [Indexed: 12/24/2022] Open
Abstract
The present study was conducted to characterize possible rapid effects of 17-β-estradiol on voltage-gated K+ channels in preoptic neurons and, in particular, to identify the mechanisms by which 17-β-estradiol affects the K+ channels. Whole-cell currents from dissociated rat preoptic neurons were studied by perforated-patch recording. 17-β-estradiol rapidly (within seconds) and reversibly reduced the K+ currents, showing an EC50 value of 9.7 µM. The effect was slightly voltage dependent, but independent of external Ca2+, and not sensitive to an estrogen-receptor blocker. Although 17-α-estradiol also significantly reduced the K+ currents, membrane-impermeant forms of estradiol did not reduce the K+ currents and other estrogens, testosterone and cholesterol were considerably less effective. The reduction induced by estradiol was overlapping with that of the KV-2-channel blocker r-stromatoxin-1. The time course of K+ current in 17-β-estradiol, with a time-dependent inhibition and a slight dependence on external K+, suggested an open-channel block mechanism. The properties of block were predicted from a computational model where 17-β-estradiol binds to open K+ channels. It was concluded that 17-β-estradiol rapidly reduces voltage-gated K+ currents in a way consistent with an open-channel block mechanism. This suggests a new mechanism for steroid action on ion channels.
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Affiliation(s)
- Michael Druzin
- Department of Integrative Medical Biology, Section for Physiology, Umeå University, Umeå, Sweden
| | - Evgenya Malinina
- Department of Integrative Medical Biology, Section for Physiology, Umeå University, Umeå, Sweden
| | - Ola Grimsholm
- Department of Integrative Medical Biology, Section for Physiology, Umeå University, Umeå, Sweden
| | - Staffan Johansson
- Department of Integrative Medical Biology, Section for Physiology, Umeå University, Umeå, Sweden
- * E-mail:
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Verrotti A, Loiacono G, Laus M, Coppola G, Chiarelli F, Tiboni GM. Hormonal and reproductive disturbances in epileptic male patients: Emerging issues. Reprod Toxicol 2011; 31:519-27. [DOI: 10.1016/j.reprotox.2011.02.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2010] [Revised: 01/12/2011] [Accepted: 02/14/2011] [Indexed: 01/23/2023]
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35
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Grassi S, Frondaroli A, Scarduzio M, Dutia MB, Dieni C, Pettorossi VE. Effects of 17beta-estradiol on glutamate synaptic transmission and neuronal excitability in the rat medial vestibular nuclei. Neuroscience 2009; 165:1100-14. [PMID: 19944747 DOI: 10.1016/j.neuroscience.2009.11.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 11/17/2009] [Indexed: 10/20/2022]
Abstract
We investigated the effects of the neurosteroid 17beta-estradiol (E(2)) on the evoked and spontaneous activity of rat medial vestibular nucleus (MVN) neurons in brainstem slices. E(2) enhances the synaptic response to vestibular nerve stimulation in type B neurons and depresses the spontaneous discharge in both type A and B neurons. The amplitude of the field potential, as well as the excitatory post-synaptic potential (EPSP) and current (EPSC), in type B neurons, are enhanced by E(2). Both effects are long-term phenomena since they outlast the drug washout. The enhancement of synaptic response is mainly due to facilitation of glutamate release mediated by pre-synaptic N-methyl-D-aspartate receptors (NMDARs), since the reduction of paired pulse ratio (PPR) and the increase of miniature EPSC frequency after E(2) are abolished under D-(-)-2-amino-5-phosphonopentanoic acid (AP-5). E(2) also facilitates post-synaptic NMDARs, but it does not affect directly alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) and group I-metabotropic glutamate receptors (mGluRs-I). In contrast, the depression of the spontaneous discharge of type A and type B neurons appears to depend on E(2) modulation of intrinsic ion conductances, as the effect remains after blockade of glutamate, GABA and glycine receptors (GlyRs). The net effect of E(2) is to enhance the signal-to-noise ratio of the synaptic response in type B neurons, relative to resting activity of all MVN neurons. These findings provide evidence for a novel potential mechanism to modulate the responsiveness of vestibular neurons to afferent inputs, and so regulate vestibular function in vivo.
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Affiliation(s)
- S Grassi
- Department of Internal Medicine, Section of Human Physiology, University of Perugia, Perugia, Italy.
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36
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Zheng P. Neuroactive steroid regulation of neurotransmitter release in the CNS: Action, mechanism and possible significance. Prog Neurobiol 2009; 89:134-52. [DOI: 10.1016/j.pneurobio.2009.07.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 03/11/2009] [Accepted: 07/02/2009] [Indexed: 12/31/2022]
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37
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Kelly MJ, Rønnekleiv OK. Control of CNS neuronal excitability by estrogens via membrane-initiated signaling. Mol Cell Endocrinol 2009; 308:17-25. [PMID: 19549588 PMCID: PMC2701913 DOI: 10.1016/j.mce.2009.03.008] [Citation(s) in RCA: 55] [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: 11/03/2008] [Revised: 02/24/2009] [Accepted: 03/05/2009] [Indexed: 10/24/2022]
Abstract
It is well known that many of the actions of 17beta-estradiol (E2) in the central nervous system (CNS) are mediated via intracellular receptor/transcription factors that interact with steroid response elements on target genes. However, there is compelling evidence for membrane-associated steroid receptors for E2 in hypothalamic and other brain neurons. Indeed, we are just beginning to understand how E2 signals via membrane receptors, and how these signals impact not only membrane excitability but also gene transcription in neurons. We know that E2 can rapidly alter neuronal activity within seconds, indicating that some cellular effects can occur via membrane-delimited events. In addition, E2 can affect second messenger systems including calcium mobilization and a plethora of kinases to alter cell signaling. This review will concentrate on rapid membrane-initiated and intracellular signaling by E2 in the hypothalamus and hippocampus, the nature of receptors involved and how they contribute to CNS functions.
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Affiliation(s)
- Martin J. Kelly
- Department of Physiology and Pharmacology, L334, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098, USA. E-mail, ; fax 503-494-4352, phone 503-494-5833
| | - Oline K. Rønnekleiv
- Department of Physiology and Pharmacology, L334, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098, USA. E-mail, ; fax 503-494-4352, phone 503-494-5833
- Department of Anesthesiology and Perioperative Medicine, L334, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098, USA. E-mail, ; fax 503-494-4352, phone 503-494-5840
- Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
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38
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Szawka RE, Rodovalho GV, Monteiro PM, Carrer HF, Anselmo-Franci JA. Ovarian-steroid modulation of locus coeruleus activity in female rats: involvement in luteinising hormone regulation. J Neuroendocrinol 2009; 21:629-39. [PMID: 19490365 DOI: 10.1111/j.1365-2826.2009.01880.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The noradrenergic nucleus locus coeruleus (LC) has been reported to regulate luteinising hormone (LH) secretion in female rats. Both oestrogen and progestin receptors have been demonstrated in LC neurones, suggesting that these cells are possibly responsive to variations in circulating levels of ovarian steroids. We therefore evaluated changes in the activity of LC neurones during the oestrous cycle and after ovarian-steroid treatment in ovariectomised (OVX) rats, as determined by immunoreactivity to Fos-related antigens (FRA), which comprises all of the known members of the Fos family. Effects of ovarian steroids on the firing rate of LC neurones were also determined in a slice preparation. The number of FRA/tyrosine hydroxylase (TH)-immunoreactive (ir) neurones in the LC increased from 14.00-16.00 h on pro-oestrus, coinciding with the onset of the LH surge and rise in plasma progesterone. FRA immunoreactivity was unaltered during dioestrus. Oestradiol-treated OVX rats (OVX+E) displayed marked reduction in FRA/TH-ir neurones in LC compared to oil-treated OVX rats. Accordingly, oestradiol superfusion significantly reduced the spontaneous firing rate of LC neurones in slices from OVX rats. Compared to OVX+E, oestradiol-treated rats injected with progesterone at 08.00 h (OVX+EP) exhibited higher number of FRA/TH-ir neurones in the LC at 10.00 h and 16.00 h, and great amplification of the LH surge. Bath application of progesterone significantly increased the spontaneous firing rate of OVX+E LC neurones. Our data suggest that ovarian steroids may physiologically modulate the activity of LC neurones in females, with possible implications for LH secretion. Moreover, oestradiol and progesterone appear to exert opposite and complementary effects (i.e. whereas oestradiol inhibits, progesterone, after oestradiol priming, stimulates LC activity).
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Affiliation(s)
- R E Szawka
- Laboratório de Neuroendocrinologia, Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirão Preto, SP, Brazil
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39
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Marin R, Díaz M, Alonso R, Sanz A, Arévalo MA, Garcia-Segura LM. Role of estrogen receptor alpha in membrane-initiated signaling in neural cells: interaction with IGF-1 receptor. J Steroid Biochem Mol Biol 2009; 114:2-7. [PMID: 19167493 DOI: 10.1016/j.jsbmb.2008.12.014] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Accepted: 12/31/2008] [Indexed: 12/25/2022]
Abstract
The mechanisms of action of estradiol in the nervous system involve nuclear-initiated steroid signaling and membrane-initiated steroid signaling. Estrogen receptors (ERs) are involved in both mechanisms. ERalpha interacts with the signaling of IGF-1 receptor in neural cells: ERalpha transcriptional activity is regulated by IGF-1 receptor signaling and estradiol regulates IGF-1 receptor signaling. The interaction between ERalpha and the IGF-1 receptor in the brain may occur at the plasma membrane of neurons and glial cells. Caveolin-1 may provide the scaffolding for the interaction of different membrane-associated molecules, including voltage-dependent anion channel, ERalpha and IGF-I receptor.
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Affiliation(s)
- Raquel Marin
- Laboratory of Cellular Neurobiology, Department of Physiology & Institute of Biomedical Technologies, University of La Laguna, School of Medicine, Santa Cruz de Tenerife, Spain
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40
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Bae JS, Sawai S, Misawa S, Kanai K, Isose S, Shibuya K, Kuwabara S. Effects of age on excitability properties in human motor axons. Clin Neurophysiol 2008; 119:2282-6. [PMID: 18760964 DOI: 10.1016/j.clinph.2008.07.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 07/09/2008] [Accepted: 07/20/2008] [Indexed: 10/21/2022]
Abstract
OBJECTIVE The threshold tracking technique is a new approach to non-invasively assess biophysical properties of axonal membrane in human subjects. The aim of this study was to evaluate the effects of age and gender on excitability properties of human motor axons. METHODS Computerized threshold tracking was used to measure multiple excitability indices in median motor axons of 93 normal subjects (50 men; age, 20-86 years). RESULTS Regression analyses showed that the higher age was associated with longer strength-duration time constant (p=0.03), smaller threshold changes in depolarizing threshold electrotonus (p=0.02), smaller supernormality (p=0.01), and steeper slope of the current-threshold relationship for hyperpolarizing currents (p<0.001). There were slight sex differences in rheobase, threshold electrotonus, supernormality, late subnormality, and current-threshold slope, though they were significant only in the subgroup with age <50 years. CONCLUSIONS Aging may increase persistent sodium currents, inward rectification, and possibly, outward potassium currents. The combination of changes raises the possibility of slight membrane depolarization in elderly people. For the sex-related differences, further studies will be required with the evaluation of sex hormonal effects. SIGNIFICANCE Age-related effects on excitability properties are subtle, but should be taken into consideration in the clinical application of nerve excitability testing, particularly in elderly subjects.
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Affiliation(s)
- Jong Seok Bae
- Department of Neurology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-8670, Japan
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41
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Kelly MJ, Rønnekleiv OK. Membrane-initiated estrogen signaling in hypothalamic neurons. Mol Cell Endocrinol 2008; 290:14-23. [PMID: 18538919 PMCID: PMC2601664 DOI: 10.1016/j.mce.2008.04.014] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Accepted: 04/11/2008] [Indexed: 10/24/2022]
Abstract
It is well known that many of the actions of 17beta-estradiol (E2) in the central nervous system are mediated via intracellular receptor/transcription factors that interact with steroid response elements on target genes. However, there is compelling evidence for membrane steroid receptors for estrogen in hypothalamic and other brain neurons. But it is not well understood how estrogen signals via membrane receptors, and how these signals impact not only membrane excitability but also gene transcription in neurons. Indeed, it has been known for sometime that E2 can rapidly alter neuronal activity within seconds, indicating that some cellular effects can occur via membrane delimited events. In addition, E2 can affect second messenger systems including calcium mobilization and a plethora of kinases to alter cell signaling. Therefore, this review will consider our current knowledge of rapid membrane-initiated and intracellular signaling by E2 in the hypothalamus, the nature of receptors involved and how they contribute to homeostatic functions.
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Affiliation(s)
- Martin J Kelly
- Department of Physiology and Pharmacology, L334, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239-3098, USA.
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42
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Estrogen receptor α is expressed on the cell-surface of embryonic hypothalamic neurons. Neuroscience 2008; 154:1173-7. [DOI: 10.1016/j.neuroscience.2008.05.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Revised: 04/11/2008] [Accepted: 05/02/2008] [Indexed: 11/19/2022]
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43
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Fatehi M, Fatehi-Hassanabad Z. Effects of 17beta-estradiol on neuronal cell excitability and neurotransmission in the suprachiasmatic nucleus of rat. Neuropsychopharmacology 2008; 33:1354-64. [PMID: 17687263 DOI: 10.1038/sj.npp.1301523] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
17beta-Estradiol receptors have been found in several brain nuclei including the suprachiasmatic nucleus (SCN) of mammalian species. The SCN is believed to act as brain clock regulating circadian and circannual biological rhythms, such as body temperature, sleep, and mood. Here, we examined whether 17beta-estradiol (E2) could affect cell excitability and synaptic transmission in the SCN. Bath application of E2 (0.03-3 microM) increased the spontaneous firing frequency and depolarized cell membrane of the SCN neurons significantly. Furthermore, E2 (0.03-3 microM) increased (by about 25-150% of control) frequency of the miniature excitatory postsynaptic currents. Amplitude of the evoked excitatory postsynaptic currents was enhanced (by about 32% of control) after exposure to 1 microM E2. The paired-pulse ratio was reduced by E2. These effects were prevented by the estrogen receptor antagonist, ICI 182780. Exposure to the biologically inactive 17alpha-estradiol did not cause any significant changes in the parameters mentioned above. These findings are in favor of an implication of estrogen in modulation of neuronal activity in SCN and possibly regulating circadian rhythms.
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Affiliation(s)
- Mohammad Fatehi
- Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada.
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Gorosito SV, Cambiasso MJ. Axogenic effect of estrogen in male rat hypothalamic neurons involves Ca(2+), protein kinase C, and extracellular signal-regulated kinase signaling. J Neurosci Res 2008; 86:145-57. [PMID: 17722067 DOI: 10.1002/jnr.21466] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
17-beta-Estradiol (E2) stimulates the growth of axons in male-derived hypothalamic neurons in vitro. This effect is not exerted through the classical intracellular estrogen receptor (ER) but depends on a membrane mechanism involving TrkB. In the present study, we investigate the intracellular signaling cascade that mediates the axogenic effect of E2. Treatment with an intracellular Ca(2+) chelator, a Ca(2+)-dependent protein kinase C (PKC) inhibitor, or two specific inhibitors of extracellular signal-regulated kinases (ERK) mitogen-activated protein kinases (MAPK) completely inhibited the E2-induced axogenesis. E2 and the membrane-impermeant construct E2BSA rapidly induced phosphorylation of ERK, which was blocked by the specific inhibitor of the ERK pathway UO126 but not by the ER antagonist ICI 182,780. Decrease of intracellular free Ca(2+) or disruption of PKC activation by Ro 32-0432 attenuated ERK activation, indicating the confluence of signals in the MAPK pathway. Subcellular analysis of ERK demonstrated that the phospho-ERK signal is augmented in the nucleus after 15 min of E2 stimulation. We have also shown that E2 increased phosphorylation of CREB via ERK signaling. In summary, this study demonstrates that E2, probably via a membrane-associated receptor, induces axonal growth by activating CREB phosphorylation through ERK signaling by a mechanism involving Ca(2+) and PKC activation.
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Affiliation(s)
- S V Gorosito
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET, Córdoba, Argentina
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Abstract
It has been known for more than 30 years that estrogen can alter the intrinsic and synaptic physiology of neurons within minutes. The physiological significance of these acute effects has been unclear, however, because some effects require higher concentrations of estrogen than are detected in plasma, and because estrogen secreted by the ovary rises and falls over a time course of days, not minutes. These concerns may be answered by new research demonstrating that estrogen is produced at high levels within the brain itself, and that production of estrogen in the brain may be regulated by neuronal activity. Additionally, recent studies indicate that classical estrogen receptor proteins are found not only in the nucleus where they regulate gene expression but also at extranuclear sites, including at synapses. These findings, together with evidence for new types of extranuclear estrogen receptors, suggest that estrogen might act directly at synapses to activate second messenger signaling, thereby rapidly altering neuronal excitability, synaptic transmission, and/or synaptic plasticity.
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Affiliation(s)
- Catherine S Woolley
- Department of Neurobiology and Physiology, Northwestern University, Evanston, IL 60208, USA.
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Fernández de Sevilla D, Fuenzalida M, Porto Pazos AB, Buño W. Selective shunting of the NMDA EPSP component by the slow afterhyperpolarization in rat CA1 pyramidal neurons. J Neurophysiol 2007; 97:3242-55. [PMID: 17329628 DOI: 10.1152/jn.00422.2006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pyramidal neuron dendrites express voltage-gated conductances that control synaptic integration and plasticity, but the contribution of the Ca(2+)-activated K(+)-mediated currents to dendritic function is not well understood. Using dendritic and somatic recordings in rat hippocampal CA1 pyramidal neurons in vitro, we analyzed the changes induced by the slow Ca(2+)-activated K(+)-mediated afterhyperpolarization (sAHP) generated by bursts of action potentials on excitatory postsynaptic potentials (EPSPs) evoked at the apical dendrites by perforant path-Schaffer collateral stimulation. Both the amplitude and decay time constants of EPSPs (tau(EPSP)) were reduced by the sAHP in somatic recordings. In contrast, the dendritic EPSP amplitude remained unchanged, whereas tau(EPSP) was reduced. Temporal summation was reduced and spatial summation linearized by the sAHP. The amplitude of the isolated N-methyl-D-aspartate component of EPSPs (EPSP(NMDA)) was reduced, whereas tau(NMDA) was unaffected by the sAHP. In contrast, the sAHP did not modify the amplitude of the isolated EPSP(AMPA) but reduced tau(AMPA) both in dendritic and somatic recordings. These changes are attributable to a conductance increase that acted mainly via a selective "shunt" of EPSP(NMDA) because they were absent under voltage clamp, not present with imposed hyperpolarization simulating the sAHP, missing when the sAHP was inhibited with isoproterenol, and reduced under block of EPSP(NMDA). EPSPs generated at the basal dendrites were similarly modified by the sAHP, suggesting both a somatic and apical dendritic location of the sAHP channels. Therefore the sAHP may play a decisive role in the dendrites by regulating synaptic efficacy and temporal and spatial summation.
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Silva A, Perrone R, Macadar O. Environmental, seasonal, and social modulations of basal activity in a weakly electric fish. Physiol Behav 2007; 90:525-36. [PMID: 17178133 DOI: 10.1016/j.physbeh.2006.11.003] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 10/26/2006] [Accepted: 11/06/2006] [Indexed: 11/23/2022]
Abstract
The electric organ discharge (EOD) of weakly electric fish encodes information about species, sex, behavioral, and physiological states throughout the lifetime. Its central command is crucial for sensory-motor coordination, and is therefore the target of plastic mechanisms that adapt fish to environmental and social challenges. The EOD waveform of Brachyhypopomus pinnicaudatus is modulated by environmental factors and the neuroendocrine system. In this study we investigate the effects of water temperature and day-night cycle upon EOD rate in this species during the breeding and non-breeding seasons. During the non-breeding season, EOD rate is a linear function of water temperature and exhibits counterclockwise hysteresis. During breeding, a thermal resistance strategy prevents the decrease of EOD rate to cooling. A nocturnal increase of EOD basal rate independent of water temperature and locomotor activity was demonstrated in isolated non-breeding adults and in male-female dyads all year round. An additional increase of nocturnal EOD rate, probably acting as a social courtship signal, was found in breeding dyads. This additional increase of nocturnal EOD rate could not be fully explained by gonadal maturation and was modulated by social stimuli. This study provides novel data on the complex interactions between environment, reproductive cycle, social behavior, and electromotor output in an advantageous model of the vertebrate central nervous system.
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Affiliation(s)
- Ana Silva
- Depto. de Neurofisiología, Instituto de Investigaciones Biológicas Clemente Estable, Unidad Asociada de Facultad de Ciencias, Universidad de la República, Avda Italia 3318, 11600 Montevideo, Uruguay.
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Huddleston GG, Paisley JC, Graham S, Grober MS, Clancy AN. Implants of estradiol conjugated to bovine serum albumin in the male rat medial preoptic area promote copulatory behavior. Neuroendocrinology 2007; 86:249-59. [PMID: 17726305 DOI: 10.1159/000107695] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2006] [Accepted: 07/06/2007] [Indexed: 12/26/2022]
Abstract
The expression of mating behavior in male rats is dependent on estrogen-responsive neurons in the medial preoptic area (MPO). Previous reports showed that mating is attenuated if the aromatization of testosterone to estradiol (E2) is blocked in the MPO and that mating is maintained by MPO E2 implants. However, the mechanisms by which E2 exerts its action are not fully understood. It had been thought that E2 acted exclusively by binding to nuclear estrogen receptors to exert it effects; however, recent reports suggest that E2 also binds to membrane-associated receptors activating downstream intracellular cascade responses. In this study, we aimed to determine if an action of E2 at the cell surface is sufficient to support mating behavior. Therefore, either vehicle, E2, or E2 conjugated to bovine serum albumin (BSA-E2: a complex of E2 and a large protein that will not cross the plasma membrane, thereby restricting the action of E2 to cell surface signaling) was chronically administered bilaterally to the MPO of castrated, dihydrotestosterone-treated male rats. Mating behavior was supported by MPO BSA-E2 implants, suggesting that E2 operates in the MPO via a cell surface mechanism to facilitate male rat mating behavior.
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Affiliation(s)
- Gloria G Huddleston
- Department of Biology, Georgia State University, Atlanta, GA 30302-4010, USA
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Mendez P, Wandosell F, Garcia-Segura LM. Cross-talk between estrogen receptors and insulin-like growth factor-I receptor in the brain: cellular and molecular mechanisms. Front Neuroendocrinol 2006; 27:391-403. [PMID: 17049974 DOI: 10.1016/j.yfrne.2006.09.001] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2006] [Revised: 08/11/2006] [Accepted: 09/01/2006] [Indexed: 01/02/2023]
Abstract
Accumulating evidence suggests that insulin-like growth factor-I (IGF-I) and estradiol interact to regulate neural function. In this review, we focus on the cellular and molecular mechanisms involved in this interaction. The expression of estrogen receptors (ERs) and IGF-I receptor is cross-regulated in the central nervous system and many neurons and astrocytes coexpress both receptors. Furthermore, estradiol activates IGF-I receptor and its intracellular signaling. This effect may involve classical ERs since recent findings suggest that ERalpha may affect IGF-I actions in the brain by a direct interaction with some of the components of IGF-I signaling. In turn, IGF-I may regulate ER transcriptional activity in neuronal cells. In conclusion, ERs appear to be part of the signaling mechanism of IGF-I, and IGF-I receptor part of the mechanism of estradiol signaling in the nervous system.
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Affiliation(s)
- Pablo Mendez
- Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), E-28002 Madrid, Spain
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