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Ryan J, Artero S, Carrière I, Scali J, Maller JJ, Meslin C, Ritchie K, Scarabin PY, Ancelin ML. Brain volumes in late life: gender, hormone treatment, and estrogen receptor variants. Neurobiol Aging 2014; 35:645-54. [DOI: 10.1016/j.neurobiolaging.2013.09.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Revised: 09/14/2013] [Accepted: 09/19/2013] [Indexed: 01/06/2023]
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Pekary AE, Sattin A. Increased TRH and TRH-like peptide release in rat brain and peripheral tissues during proestrus/estrus. Peptides 2014; 52:1-10. [PMID: 24296042 DOI: 10.1016/j.peptides.2013.11.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 11/21/2013] [Accepted: 11/21/2013] [Indexed: 12/24/2022]
Abstract
Women are at greater risk for major depression, PTSD, and other anxiety disorders. ERβ-selective agonists for the treatment of these disorders are the focus of pharmacologic development and clinical testing. Estradiol and its metabolites contribute to the neuroprotective effects of this steroid class, particularly in men, due to local conversion of testosterone to estiradiol in key brain regions which are predisposed to neurodegenerative diseases. We have used young adult female Sprague-Dawley rats to assess the role of TRH and TRH-like peptides, with the general structure pGlu-X-Pro-NH2 where "X" can be any amino acid residue, as mediators of the neurobiochemical effects of estradiol. The neuroprotective TRH and TRH-like peptides are coreleased with excitotoxic glutamate by glutamatergic neurons which contribute importantly to the regulation of the estrus cycle. The levels of TRH and TRH-like peptides during proestrus and/or estrus in the 12 brain regions analyzed were significantly decreased (due to accelerated release) 106 times but increased only 25 times when compared to the corresponding levels during diestrus days 1 and 2. These changes, listed by brain region in the order of decreasing number of significant decreases (↓) and/or increases (↑), were: striatum (20↓,1↑), medulla oblongata (16↓,2↑), amygdala (14↓,1↑), cerebellum (13↓,1↑), hypothalamus (12↓,1↑), entorhinal cortex (6↓,6↑), posterior cingulate (10↓,1↑), frontal cortex (3↓,5↑), nucleus accumbens (5↓,3↑), hippocampus (5↓,2↑), anterior cingulate (2↓,1↑), and piriform cortex (1↑). In peripheral tissues the corresponding changes were: ovaries (23↓), uterus (16↓,1↑), adrenals (11↓,3↑), and pancreas (1↓,6↑). We conclude that these peptides may be downstream mediators of some of the therapeutic effects of estrogen.
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Affiliation(s)
- A E Pekary
- Research Service, VA Greater Los Angeles Healthcare System, United States; Center for Ulcer Research and Education, VA Greater Los Angeles Healthcare System, United States; Department of Medicine, University of California, Los Angeles, CA 90073, United States.
| | - Albert Sattin
- Research Service, VA Greater Los Angeles Healthcare System, United States; Psychiatry Service, VA Greater Los Angeles Healthcare System, United States; Department of Psychiatry & Biobehavioral Sciences, University of California, Los Angeles, CA 90073, United States; Brain Research Institute, University of California, Los Angeles, CA 90073, United States
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53
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Clark S, Rainville J, Zhao X, Katzenellenbogen BS, Pfaff D, Vasudevan N. Estrogen receptor-mediated transcription involves the activation of multiple kinase pathways in neuroblastoma cells. J Steroid Biochem Mol Biol 2014; 139:45-53. [PMID: 24121066 DOI: 10.1016/j.jsbmb.2013.09.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 09/15/2013] [Accepted: 09/20/2013] [Indexed: 11/22/2022]
Abstract
While many physiological effects of estrogens (E) are due to regulation of gene transcription by liganded estrogen receptors (ERs), several effects are also mediated, at least in part, by rapid non-genomic actions of E. Though the relative importance of rapid versus genomic effects in the central nervous system is controversial, we showed previously that membrane-limited effects of E, initiated by an estradiol bovine serum albumin conjugate (E2-BSA), could potentiate transcriptional effects of 17β-estradiol from an estrogen response element (ERE)-reporter in neuroblastoma cells. Here, using specific inhibitors and activators in a pharmacological approach, we show that activation of phosphatidylinositol-3-phosphate kinase (PI3K) and mitogen activated protein kinase (MAPK) pathways, dependent on a Gαq coupled receptor signaling are important in this transcriptional potentiation. We further demonstrate, using ERα phospho-deficient mutants, that E2-BSA mediated phosphorylation of ERα is one mechanism to potentiate transcription from an ERE reporter construct. This study provides a possible mechanism by which signaling from the membrane is coupled to transcription in the nucleus, providing an integrated view of hormone signaling in the brain.
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Affiliation(s)
- Sara Clark
- Cell and Molecular Biology Department, Tulane University, New Orleans, LA 70118, United States
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Al-Rahbi B, Zakaria R, Othman Z, Hassan A, Mohd Ismail ZI, Muthuraju S. Tualang honey supplement improves memory performance and hippocampal morphology in stressed ovariectomized rats. Acta Histochem 2014; 116:79-88. [PMID: 23810156 DOI: 10.1016/j.acthis.2013.05.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Revised: 05/13/2013] [Accepted: 05/16/2013] [Indexed: 01/07/2023]
Abstract
Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed sham-operated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17β-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rats.
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Affiliation(s)
- Badriya Al-Rahbi
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia
| | - Rahimah Zakaria
- Department of Physiology, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia.
| | - Zahiruddin Othman
- Department of Psychiatry, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia
| | - Asma Hassan
- Department of Anatomy, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia
| | - Zul Izhar Mohd Ismail
- Department of Anatomy, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia
| | - Sangu Muthuraju
- Department of Neuroscience, School of Medical Sciences, Universiti Sains Malaysia Health Campus, 16150 Kubang Kerian, Malaysia
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55
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Ryan J, Carrière I, Amieva H, Rouaud O, Berr C, Ritchie K, Scarabin PY, Ancelin ML. Prospective analysis of the association between estrogen receptor gene variants and the risk of cognitive decline in elderly women. Eur Neuropsychopharmacol 2013; 23:1763-8. [PMID: 23932494 DOI: 10.1016/j.euroneuro.2013.06.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 06/19/2013] [Accepted: 06/24/2013] [Indexed: 10/26/2022]
Abstract
A plethora of data suggests a role for estrogen in cognitive function and genetic variants in the estrogen receptors ESR1 and ESR2 have been implicated in a range of hormone-sensitive diseases. It remains unknown however, whether ESR polymorphisms are associated with the risk of decline in specific domains of cognitive function. Data came from 3799 non-demented, community-dwelling elderly women recruited in France to the 3C Study. A short cognitive test battery was administered at baseline and 2, 4 and 7 years follow-up to assess global function, verbal fluency, visual memory, psychomotor speed and executive function. Detailed socio-demographic, behavioral, physical and mental health information was also gathered and genotyping of five common ESR1 and ESR2 polymorphisms was also performed. In multivariable-adjusted Cox analysis, ESR1 rs2234693 and rs9340799 were not significantly associated with the risk of decline on any of the cognitive tasks. However, significant associations with ESR2 polymorphisms were identified. The A allele of rs1256049 was associated with an increased risk of substantial decline in visual memory (HR:1.64, 95% CI: 1.23-2.18, p=0.0007), psychomotor speed (HR:1.43, 95% CI: 1.12-1.83, p=0.004), and on the incidence of Mild Cognitive Impairment (HR:1.31, 95% CI: 1.05-1.64, p=0.02). There was also a weaker association between the A allele of rs4986938 and a decreased risk of decline in psychomotor speed. Our large multicentre prospective study provides preliminary evidence that ESR2 genetic variants may be associated with specific cognitive domains and suggests that further examination of the role of this gene in cognitive function is warranted.
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Affiliation(s)
- Joanne Ryan
- Inserm, U1061, Neuropsychiatry: Epidemiological and Clinical Research, Montpellier F-34093, France; Université Montpellier1, Montpellier F-34000, France; Cancer & Disease Epigenetics, Murdoch Children's Research Institute, Flemington Road Parkville, 3052 Victoria, Australia.
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56
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Borah A, Paul R, Choudhury S, Choudhury A, Bhuyan B, Das Talukdar A, Dutta Choudhury M, Mohanakumar KP. Neuroprotective potential of silymarin against CNS disorders: insight into the pathways and molecular mechanisms of action. CNS Neurosci Ther 2013; 19:847-53. [PMID: 24118806 PMCID: PMC6493565 DOI: 10.1111/cns.12175] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 08/07/2013] [Accepted: 08/07/2013] [Indexed: 12/14/2022] Open
Abstract
Silymarin, a C25 containing flavonoid from the plant Silybum marianum, has been the gold standard drug to treat liver disorders associated with alcohol consumption, acute and chronic viral hepatitis, and toxin-induced hepatic failures since its discovery in 1960. Apart from the hepatoprotective nature, which is mainly due to its antioxidant and tissue regenerative properties, Silymarin has recently been reported to be a putative neuroprotective agent against many neurologic diseases including Alzheimer's and Parkinson's diseases, and cerebral ischemia. Although the underlying neuroprotective mechanism of Silymarin is believed to be due to its capacity to inhibit oxidative stress in the brain, it also confers additional advantages by influencing pathways such as β-amyloid aggregation, inflammatory mechanisms, cellular apoptotic machinery, and estrogenic receptor mediation. In this review, we have elucidated the possible neuroprotective effects of Silymarin and the underlying molecular events, and suggested future courses of action for its acceptance as a CNS drug for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Anupom Borah
- Cellular and Molecular Neurobiology LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Rajib Paul
- Cellular and Molecular Neurobiology LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Sabanum Choudhury
- Cellular and Molecular Neurobiology LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Amarendranath Choudhury
- Cellular and Molecular Neurobiology LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Bornalee Bhuyan
- Ethnobotany and Medicinal Plant LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Anupam Das Talukdar
- Ethnobotany and Medicinal Plant LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
| | - Manabendra Dutta Choudhury
- Ethnobotany and Medicinal Plant LaboratoryDepartment of Life Science and BioinformaticsAssam UniversitySilcharIndia
- Assam University Biotech Hub (DBT)Assam UniversitySilcharIndia
| | - Kochupurackal P Mohanakumar
- Laboratory of Clinical & Experimental NeuroscienceDivision of Cell Biology & PhysiologyCSIR‐Indian Institute of Chemical BiologyJadavpurIndia
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57
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Dietrich AK, Humphreys GI, Nardulli AM. 17β-estradiol increases expression of the oxidative stress response and DNA repair protein apurinic endonuclease (Ape1) in the cerebral cortex of female mice following hypoxia. J Steroid Biochem Mol Biol 2013; 138:410-20. [PMID: 23907014 PMCID: PMC3825811 DOI: 10.1016/j.jsbmb.2013.07.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 07/18/2013] [Accepted: 07/22/2013] [Indexed: 01/07/2023]
Abstract
While it is well established that 17β-estradiol (E2) protects the rodent brain from ischemia-induced damage, it has been unclear how this neuroprotective effect is mediated. Interestingly, convincing evidence has also demonstrated that maintaining or increasing the expression of the oxidative stress response and DNA repair protein apurinic endonuclease 1 (Ape1) is instrumental in reducing ischemia-induced damage in the brain. Since E2 increases expression of the oxidative stress response proteins Cu/Zn superoxide dismutase and thioredoxin in the brain, we hypothesized that E2 may also increase Ape1 expression and that this E2-induced expression of Ape1 may help to mediate the neuroprotective effects of E2 in the brain. To test this hypothesis, we utilized three model systems including primary cortical neurons, brain slice cultures, and whole animals. Although estrogen receptor α and Ape1 were expressed in primary cortical neurons, E2 did not alter Ape1 expression in these cells. However, immunofluorescent staining and quantitative Western blot analysis demonstrated that estrogen receptor α and Ape1 were expressed in the nuclei of cortical neurons in brain slice cultures and that E2 increased Ape1 expression in the cerebral cortex of these cultures. Furthermore, Ape1 expression was increased and oxidative DNA damage was decreased in the cerebral cortices of ovariectomized female C57Bl/6J mice that had been treated with E2 and exposed to hypoxia. Taken together, our studies demonstrate that the neuronal microenvironment may be required for increased Ape1 expression and that E2 enhances expression of Ape1 and reduces oxidative DNA damage, which may in turn help to reduce ischemia-induced damage in the cerebral cortex and mediate the neuroprotective effects of E2.
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Affiliation(s)
- Alicia K Dietrich
- Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
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58
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Dasgupta S, Bandyopadhyay M. Neuroprotective mode of action of resveratrol in central nervous system. PHARMANUTRITION 2013. [DOI: 10.1016/j.phanu.2013.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Winkler JM, Fox HS. Transcriptome meta-analysis reveals a central role for sex steroids in the degeneration of hippocampal neurons in Alzheimer's disease. BMC SYSTEMS BIOLOGY 2013; 7:51. [PMID: 23803348 PMCID: PMC3702487 DOI: 10.1186/1752-0509-7-51] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 06/19/2013] [Indexed: 11/12/2022]
Abstract
Background Alzheimer’s disease is the most prevalent form of dementia. While a number of transcriptomic studies have been performed on the brains of Alzheimer’s specimens, no clear picture has emerged on the basis of neuronal transcriptional alterations linked to the disease. Therefore we performed a meta-analysis of studies comparing hippocampal neurons in Alzheimer’s disease to controls. Results Homeostatic processes, encompassing control of gene expression, apoptosis, and protein synthesis, were identified as disrupted during Alzheimer’s disease. Focusing on the genes carrying out these functions, a protein-protein interaction network was produced for graph theory and cluster exploration. This approach identified the androgen and estrogen receptors as key components and regulators of the disrupted homeostatic processes. Conclusions Our systems biology approach was able to identify the importance of the androgen and estrogen receptors in not only homeostatic cellular processes but also the role of other highly central genes in Alzheimer’s neuronal dysfunction. This is important due to the controversies and current work concerning hormone replacement therapy in postmenopausal women, and possibly men, as preventative approaches to ward off this neurodegenerative disorder.
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Affiliation(s)
- Jessica M Winkler
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198, USA
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60
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Baudry M, Bi X, Aguirre C. Progesterone-estrogen interactions in synaptic plasticity and neuroprotection. Neuroscience 2013; 239:280-94. [PMID: 23142339 PMCID: PMC3628409 DOI: 10.1016/j.neuroscience.2012.10.051] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 10/23/2012] [Accepted: 10/26/2012] [Indexed: 01/01/2023]
Abstract
17ß-Estradiol and progesterone exert a number of physiological effects throughout the brain due to interactions with several types of receptors belonging to the traditional family of intracellular hormonal receptors as well as to membrane-bound receptors. In particular, both hormones elicit rapid modifications of neuronal excitability that have been postulated to underlie their effects on synaptic plasticity and learning and memory. Likewise, both hormones have been shown to be neuroprotective under certain conditions, possibly due to the activation of pro-survival pathways and the inhibition of pro-apoptotic cascades. Because of the similarities in their cellular effects, there have been a number of questions raised by numerous observations that progesterone inhibits the effects of estrogen. In this manuscript, we first review the interactions between 17ß-estradiol (E2) and progesterone (P4) in synaptic plasticity, and conclude that, while E2 exerts a clear and important role in long-term potentiation of synaptic transmission in hippocampal neurons, the role of P4 is much less clear, and could be accounted by the direct or indirect regulation of GABAA receptors. We then discuss the neuroprotective roles of both hormones, in particular against excitotoxicity. In this case, the neuroprotective effects of these hormones are very similar to those of the neurotrophic factor BDNF. Interestingly, P4 antagonizes the effects of E2, possibly through the regulation of estrogen receptors or of proteins associated with the receptors or interactions with signaling pathways activated by E2. Overall, this review emphasizes the existence of common molecules and pathways that participate in the regulation of both synaptic plasticity and neurodegeneration.
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Affiliation(s)
- M Baudry
- GCBS and COMP, Western University of Health Sciences, Pomona, CA, USA.
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61
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Yamazaki T, Yamamoto M, Ishihara Y, Komatsu S, Munetsuna E, Onizaki M, Ishida A, Kawato S, Mukuda T. De novo synthesized estradiol protects against methylmercury-induced neurotoxicity in cultured rat hippocampal slices. PLoS One 2013; 8:e55559. [PMID: 23405170 PMCID: PMC3566000 DOI: 10.1371/journal.pone.0055559] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 12/27/2012] [Indexed: 11/24/2022] Open
Abstract
Background Estrogen, a class of female sex steroids, is neuroprotective. Estrogen is synthesized in specific areas of the brain. There is a possibility that the de novo synthesized estrogen exerts protective effect in brain, although direct evidence for the neuroprotective function of brain-synthesized estrogen has not been clearly demonstrated. Methylmercury (MeHg) is a neurotoxin that induces neuronal degeneration in the central nervous system. The neurotoxicity of MeHg is region-specific, and the molecular mechanisms for the selective neurotoxicity are not well defined. In this study, the protective effect of de novo synthesized 17β-estradiol on MeHg-induced neurotoxicity in rat hippocampus was examined. Methodology/Principal Findings Neurotoxic effect of MeHg on hippocampal organotypic slice culture was quantified by propidium iodide fluorescence imaging. Twenty-four-hour treatment of the slices with MeHg caused cell death in a dose-dependent manner. The toxicity of MeHg was attenuated by pre-treatment with exogenously added estradiol. The slices de novo synthesized estradiol. The estradiol synthesis was not affected by treatment with 1 µM MeHg. The toxicity of MeHg was enhanced by inhibition of de novo estradiol synthesis, and the enhancement of toxicity was recovered by the addition of exogenous estradiol. The neuroprotective effect of estradiol was inhibited by an estrogen receptor (ER) antagonist, and mimicked by pre-treatment of the slices with agonists for ERα and ERβ, indicating the neuroprotective effect was mediated by ERs. Conclusions/Significance Hippocampus de novo synthesized estradiol protected hippocampal cells from MeHg-induced neurotoxicity via ERα- and ERβ-mediated pathways. The self-protective function of de novo synthesized estradiol might be one of the possible mechanisms for the selective sensitivity of the brain to MeHg toxicity.
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Affiliation(s)
- Takeshi Yamazaki
- Laboratory of Molecular Brain Science, Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashi-Hiroshima, Japan.
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Neuroprotective Effects of Estradiol on Motoneurons in a Model of Rat Spinal Cord Embryonic Explants. Cell Mol Neurobiol 2013; 33:421-32. [DOI: 10.1007/s10571-013-9908-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Accepted: 01/05/2013] [Indexed: 12/12/2022]
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Fernandez JW, Grizzell JA, Wecker L. The role of estrogen receptor β and nicotinic cholinergic receptors in postpartum depression. Prog Neuropsychopharmacol Biol Psychiatry 2013; 40:199-206. [PMID: 23063492 DOI: 10.1016/j.pnpbp.2012.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 10/02/2012] [Accepted: 10/02/2012] [Indexed: 01/19/2023]
Abstract
Postpartum depression (PPD) is a devastating disease occurring in approximately 20% of women. Women who suffer from PPD appear to be more sensitive to postpartum hormonal changes than women who do not experience this form of depression. Furthermore, women who quit smoking prior to or during pregnancy, and who develop PPD, are at an increased risk of smoking relapse. Unfortunately, the mechanistic relationship between the pathophysiology of PPD and smoking relapse is unknown. Here we review the roles of both estrogen receptor beta (ERβ) and cholinergic nicotinic receptors (nAChRs) in the pathogenesis of depression and propose a mechanistic rationale to explain the high rate of smoking relapse exhibited by women who develop PPD.
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Affiliation(s)
- Jamie Winderbaum Fernandez
- Department of Psychiatry and Behavioral Neurosciences, Morsani College of Medicine, University of South Florida, 3515 E. Fletcher Avenue, Tampa, FL, 33611, USA.
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Chamniansawat S, Chongthammakun S. A priming role of local estrogen on exogenous estrogen-mediated synaptic plasticity and neuroprotection. Exp Mol Med 2012; 44:403-11. [PMID: 22510730 PMCID: PMC3389079 DOI: 10.3858/emm.2012.44.6.046] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The localization of estrogen (E2) has been clearly shown in hippocampus, called local hippocampal E2. It enhanced neuronal synaptic plasticity and protected neuron form cerebral ischemia, similar to those effects of exogenous E2. However, the interactive function of hippocampal and exogenous E2 on synaptic plasticity activation and neuroprotection is still elusive. By using hippocampal H19-7 cells, we demonstrated the local hippocampal E2 that totally suppressed by aromatase inhibitor anastrozole. Anastrozole also suppressed estrogen receptor (ER)β, but not ERα, expression. Specific agonist of ERα (PPT) and ERβ (DPN) restored ERβ expression in anastrozole-treated cells. In combinatorial treatment with anastrozole and phosphoinositide kinase-3 (PI-3K) signaling inhibitor wortmannin, PPT could not improve hippocampal ERβ expression. On the other hand, DPN induced basal ERβ translocalization into nucleus of anastrozole-treated cells. Exogenous E2 increased synaptic plasticity markers expression in H19-7 cells. However, exogenous E2 could not enhance synaptic plasticity in anastrozole-treated group. Exogenous E2 also increased cell viability and B-cell lymphoma 2 (Bcl2) expression in H2O2-treated cells. In combined treatment of anastrozole and H2O2, exogenous E2 failed to enhance cell viability and Bcl2 expression in hippocampal H19-7 cells. Our results provided the evidence of the priming role of local hippocampal E2 on exogenous E2-enhanced synaptic plasticity and viability of hippocampal neurons.
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65
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Jeong HG, Ham BJ, Yeo HB, Jung IK, Joe SH. Gray matter abnormalities in patients with premenstrual dysphoric disorder: an optimized voxel-based morphometry. J Affect Disord 2012; 140:260-7. [PMID: 22381950 DOI: 10.1016/j.jad.2012.02.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 02/06/2012] [Accepted: 02/06/2012] [Indexed: 01/24/2023]
Abstract
BACKGROUND Although brain neurochemistry is thought to play a role in the development of premenstrual dysphoric disorder (PMDD), neuroimaging studies of PMDD are sparse. We examined the extent to which gray matter (GM) abnormalities were present in women with PMDD compared to healthy controls. METHODS 3.0T magnetic resonance imaging scans of 15 women with PMDD and 15 healthy controls were compared using optimized voxel-based morphometry (VBM) analysis. A regression analysis was used to assess the relationship between GM density and PMDD-symptom severity. RESULTS Our results showed significantly increased GM density in the hippocampal cortex and significantly decreased GM density in the parahippocampal cortex among women with PMDD compared to healthy controls. However, these GM abnormalities were not significantly associated with the severity of PMDD. LIMITATION Our inferences of the relationships between structural alterations and PMDD are drawn from a small sample, which may have increased the likelihood of type I error. CONCLUSIONS GM abnormalities in limbic and paralimbic cortices were found to be associated with the pathophysiology of PMDD. Etiology of PMDD is likely related to emotional processing and self-regulation. Our findings provide a basis of neurobiological model for PMDD.
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Affiliation(s)
- Hyun-Ghang Jeong
- Department of Psychiatry, Korea University Guro Hospital, Korea University College of Medicine, Seoul, South Korea
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66
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Liu SB, Zhao MG. Neuroprotective effect of estrogen: role of nonsynaptic NR2B-containing NMDA receptors. Brain Res Bull 2012; 93:27-31. [PMID: 23085545 DOI: 10.1016/j.brainresbull.2012.10.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 10/07/2012] [Accepted: 10/09/2012] [Indexed: 01/19/2023]
Abstract
Excessive activation of N-methyl-D-aspartate receptors (NMDARs) has been implicated in the pathophysiology of chronic neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, and Huntington's disease. Some studies reported that NR2A and NR2B play different roles in the central nervous system (CNS). The NR2A subunit is primarily found in the synapses and is required for glutamate-mediated neuronal survival. On the other hand, the NR2B subunit is primarily found in the extrasynaptic sites and is required for glutamate-mediated neuronal death in both in vitro and in vivo experiments. Estrogen is a steroid hormone well known for its widespread effects such as neuroprotection in the brain. Classically, estrogen can bind to two kinds of nuclear receptors, namely, estrogen receptor α (ERα) and estrogen receptor β (ERβ), and produce physiological and neuroprotective effects. Aside from nuclear receptors, estrogen has one membrane receptor, which can either be G-protein-coupled receptor 30 (GPR30), Gq-mER, or ER-X. NMDA exposure clearly promotes NR2B subunit phosphorylation at Ser-1303 and causes neuronal cell death. GPR30 mediates rapid non-genomic effects to protect neurons against injury by inhibiting p-DAPK1 dephosphorylation, which inhibits NR2B subunit phosphorylation at Ser-1303. In addition, NMDA exposure and global ischemia activate the autophagy pathway and induce cell death, which are markedly blocked by the NR2B antagonist Ro 25-6981. Thus, NR2B signaling, autophagy induction and cell death may be closely related. Ro 25-6981 inhibits the dissociation of the NR2B-Beclin-1 signaling complex and delays autophagy in vivo, thus confirming the link between NR2B signaling and autophagy. In short, ERα, ERβ, and GPR30 are involved in the neuroprotection of estrogen in the CNS. Additional research must be conducted to reveal the mechanism of estrogen action fully and to identify better targets for the development of more effective drugs. This article is part of a Special Issue entitled 'Extrasynaptic ionotropic receptors'.
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Affiliation(s)
- Shui-bing Liu
- Department of Pharmacology, School of Pharmacy, Fourth Military Medical University, Xi'an 710032, Shaanxi, China
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67
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Simpkins JW, Singh M, Brock C, Etgen AM. Neuroprotection and estrogen receptors. Neuroendocrinology 2012; 96:119-30. [PMID: 22538356 PMCID: PMC6507404 DOI: 10.1159/000338409] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 03/18/2012] [Indexed: 11/19/2022]
Abstract
This review is intended to assess the state of current knowledge on the role of estrogen receptors (ERs) in the neuroprotective effects of estrogens in models for acute neuronal injury and death. We evaluate the overall evidence that estrogens are neuroprotective in acute injury and critically assess the role of ERα, ERβ, GPR 30, and nonreceptor-mediated mechanisms in these robust neuroprotective effects of this ovarian steroid hormone. We conclude that all three receptors, as well as nonreceptor-mediated mechanisms can be involved in neuroprotection, depending on the model used, the level of estrogen administrated, and the mode of administration of the steroid. Also, the signaling pathways used by both ER-dependent and ER-independent mechanisms to exert neuroprotection are considered. Finally, further studies that are needed to parse out the relative contribution of receptor versus nonreceptor-mediated signaling are discussed.
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Affiliation(s)
- James W. Simpkins
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer’s Disease Research, University of North Texas Health Science Center, Fort Worth, TX 76107
| | - Meharvan Singh
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer’s Disease Research, University of North Texas Health Science Center, Fort Worth, TX 76107
| | - Courtney Brock
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer’s Disease Research, University of North Texas Health Science Center, Fort Worth, TX 76107
| | - Anne M. Etgen
- Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Forchheimer Building, Room 113, Bronx, NY 10461
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68
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Arnold S. Cytochrome c oxidase and its role in neurodegeneration and neuroprotection. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 748:305-39. [PMID: 22729864 DOI: 10.1007/978-1-4614-3573-0_13] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A hallmark of neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases, and stroke is a malfunction of mitochondria including cytochrome c oxidase (COX), the terminal enzyme complex of the respiratory chain. COX is ascribed a key role based on mainly two regulatory mechanisms. These are the expression of isoforms and the binding of specific allosteric factors to nucleus--encoded subunits. These characteristics represent a unique feature of COX compared with the other respiratory chain complexes. Additional regulatory mechanisms, such as posttranslational modification, substrate availability, and allosteric feedback inhibition by products of the COX reaction, control the enzyme activity in a complex way. In many tissues and cell types, COX represents the rate-limiting enzyme of the respiratory chain which further emphasizes the impact of the regulation of COX as a central site for regulating energy metabolism and oxidative stress. Two of the best-analyzed regulatory mechanisms of COX to date are the allosteric feedback inhibition of the enzyme by its indirect product ATP and the expression of COX subunit IV isoforms. This ATP feedback inhibition of COX requires the expression of COX isoform IV-1. At high ATP/ADP ratios, ADP is exchanged for ATP at the matrix side of COX IV-1 leading to an inhibition of COX activity, thus enabling COX to sense the energy level and to adjust ATP synthesis to energy demand. However, under hypoxic, toxic, and degenerative conditions, COX isoform IV-2 expression is up-regulated and exchanged for COX IV-1 in the enzyme complex. This COX IV isoform switch causes an abolition of the allosteric ATP feedback inhibition of COX and consequently the loss of sensing the energy level. Thus, COX activity is increased leading to higher levels of ATP in neural cells independently of the cellular energy level. Concomitantly, ROS production is increased. Thus, under pathological conditions, neural cells are provided with ATP to meet the energy demand, but at the expense of elevated oxidative stress. This mechanism explains the functional relevance of COX subunit IV isoform expression for cellular energy sensing, ATP production, and oxidative stress levels. This, in turn, affects neural cell function, signaling, and -survival. Thus, COX is a crucial factor in etiology, progression, and prevalence of numerous human neurodegenerative diseases and represents an important target for developing diagnostic and therapeutic tools against those diseases.
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Affiliation(s)
- Susanne Arnold
- Institute for Neuroanatomy, RWTH Aachen University, Wendlingweg 2, Aachen, Germany.
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Lee E, Sidoryk-Wegrzynowicz M, Yin Z, Webb A, Son DS, Aschner M. Transforming growth factor-α mediates estrogen-induced upregulation of glutamate transporter GLT-1 in rat primary astrocytes. Glia 2012; 60:1024-36. [PMID: 22488924 PMCID: PMC3353324 DOI: 10.1002/glia.22329] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 02/28/2012] [Indexed: 01/02/2023]
Abstract
Glutamate transporter-1 (GLT-1) plays a central role in preventing excitotoxicity by removing excess glutamate from the synaptic clefts. 17β-Estradiol (E2) and tamoxifen (TX), a selective estrogen receptor (ER) modulator, afford neuroprotection in a range of experimental models. However, the mechanisms that mediate E2 and TX neuroprotection have yet to be elucidated. We tested the hypothesis that E2 and TX enhance GLT-1 function by increasing transforming growth factor (TGF)-α expression and, thus, attenuate manganese (Mn)-induced impairment in astrocytic GLT-1 expression and glutamate uptake in rat neonatal primary astrocytes. The results showed that E2 (10 nM) and TX (1 μM) increased GLT-1 expression and reversed the Mn-induced reduction in GLT-1, both at the mRNA and protein levels. E2/TX also concomitantly reversed the Mn-induced inhibition of astrocytic glutamate uptake. E2/TX activated the GLT-1 promoter and attenuated the Mn-induced repression of the GLT-1 promoter in astrocytes. TGF-α knockdown (siRNA) abolished the E2/TX effect on GLT-1 expression, and inhibition of epidermal growth factor receptor (TGF-α receptor) suppressed the effect of E2/TX on GLT-1 expression and GLT-1 promoter activity. E2/TX also increased TGF-α mRNA and protein levels with a concomitant increase in astrocytic glutamate uptake. All ERs (ER-α, ER-β, and G protein-coupled receptor 30) were involved in mediating E2 effects on the regulation of TGF-α, GLT-1, and glutamate uptake. These results indicate that E2/TX increases GLT-1 expression in astrocytes via TGF-α signaling, thus offering an important putative target for the development of novel therapeutics for neurological disorders.
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Affiliation(s)
- Eunsook Lee
- Department of Physiology, Meharry Medical College, Nashville, TN 37208, USA.
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Adams SM, Aksenova MV, Aksenov MY, Mactutus CF, Booze RM. Soy isoflavones genistein and daidzein exert anti-apoptotic actions via a selective ER-mediated mechanism in neurons following HIV-1 Tat(1-86) exposure. PLoS One 2012; 7:e37540. [PMID: 22629415 PMCID: PMC3358258 DOI: 10.1371/journal.pone.0037540] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 04/24/2012] [Indexed: 01/02/2023] Open
Abstract
Background HIV-1 viral protein Tat partially mediates the neural dysfunction and neuronal cell death associated with HIV-1 induced neurodegeneration and neurocognitive disorders. Soy isoflavones provide protection against various neurotoxic insults to maintain neuronal function and thus help preserve neurocognitive capacity. Methodology/Principal Findings We demonstrate in primary cortical cell cultures that 17β-estradiol or isoflavones (genistein or daidzein) attenuate Tat1–86-induced expression of apoptotic proteins and subsequent cell death. Exposure of cultured neurons to the estrogen receptor antagonist ICI 182,780 abolished the anti-apoptotic actions of isoflavones. Use of ERα or ERβ specific antagonists determined the involvement of both ER isoforms in genistein and daidzein inhibition of caspase activity; ERβ selectively mediated downregulation of mitochondrial pro-apoptotic protein Bax. The findings suggest soy isoflavones effectively diminished HIV-1 Tat-induced apoptotic signaling. Conclusions/Significance Collectively, our results suggest that soy isoflavones represent an adjunctive therapeutic option with combination anti-retroviral therapy (cART) to preserve neuronal functioning and sustain neurocognitive abilities of HIV-1 infected persons.
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Affiliation(s)
- Sheila M Adams
- Department of Psychology, University of South Carolina, Columbia, South Carolina, United States of America.
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71
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Foster TC. Role of estrogen receptor alpha and beta expression and signaling on cognitive function during aging. Hippocampus 2012; 22:656-69. [PMID: 21538657 PMCID: PMC3704216 DOI: 10.1002/hipo.20935] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/06/2011] [Indexed: 12/24/2022]
Abstract
This review presents evidence for the idea that the expression of estrogen receptor alpha and beta (ERα and ERβ) interacts with the level of estradiol (E2) to influence the etiology of age-related cognitive decline and responsiveness to E2 treatments. There is a nonmonotonic dose response curve for E2 influences on behavior and transcription. Evidence is mounting to indicate that the dose response curve is shifted according to the relative expression of ERα and ERβ. Recent work characterizing age-related changes in the expression of ERα and ERβ in the hippocampus, as well as studies using mutant mice, and viral mediated delivery of estrogen receptors indicate that an age-related shift in ERα/ERβ expression, combined with declining gonadal E2 can impact transcription, cell signaling, neuroprotection, and neuronal growth. Finally, the role of ERα/ERβ on rapid E2 signaling and synaptogenesis as it relates to hippocampal aging is discussed.
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Affiliation(s)
- Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610-0244, USA.
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72
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Estrogen receptor β-selective phytoestrogenic formulation prevents physical and neurological changes in a preclinical model of human menopause. Menopause 2012; 18:1131-42. [PMID: 21738079 DOI: 10.1097/gme.0b013e3182175b66] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE As an alternative to estrogen therapy, the efficacy of an estrogen receptor β-selective phytoestrogenic (phyto-β-SERM) formulation to regulate climacteric symptoms and decline in brain responses associated with ovarian hormone loss in menopause was assessed. METHODS A phyto-β-SERM formulation-containing diet was compared with a commercial soy extract diet and a phytoestrogen-free base/control diet in an ovariectomized (OVX) mouse model of human menopause. Two treatment studies were conducted: (1) a 2-month study assessed the effects of experimental diets on tail skin temperature as a model of menopausal hot flashes, and (2) a 9-month study assessed the long-term impact of the diets on overall health, hair thinning/loss, spatial working memory, and associated protein expression in the hippocampus. RESULTS The phyto-β-SERM diet prevented OVX-induced menopause-like changes including the rise in skin temperature, hair thinning/loss, deficit in spatial memory function, and reversed OVX-induced decline in the expression of hippocampal proteins involved in neural plasticity and β-amyloid degradation/clearance. The soy extract diet had no effect or exacerbated OVX-induced changes. CONCLUSIONS Overall, the phyto-β-SERM diet induced physical and neurological responses comparable with ovary-intact mice, suggesting the therapeutic potential of the phyto-β-SERM formulation for the prevention/alleviation of climacteric symptoms and decline in brain responses induced by ovarian hormone loss, which provides the basis for further work in postmenopausal women.
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73
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Raval AP, Dave KR, Saul I, Gonzalez GJ, Diaz F. Synergistic inhibitory effect of nicotine plus oral contraceptive on mitochondrial complex-IV is mediated by estrogen receptor-β in female rats. J Neurochem 2012; 121:157-67. [DOI: 10.1111/j.1471-4159.2012.07661.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Durham JL, Jordan KA, Devos MJ, Williams EK, Sandstrom NJ. Estradiol protects against hippocampal damage and impairments in fear conditioning resulting from transient global ischemia in mice. Brain Res 2012; 1443:64-74. [PMID: 22305144 DOI: 10.1016/j.brainres.2012.01.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Revised: 12/12/2011] [Accepted: 01/07/2012] [Indexed: 01/02/2023]
Abstract
Estradiol protects against hippocampal damage and some learning impairments resulting from transient global ischemia in rats. Here, we seek to validate a mouse model of transient global ischemia and evaluate the effects of estradiol on ischemia-induced hippocampal damage and behavioral impairments. Female C57Bl6/J mice were ovariectomized and implanted with estradiol- or oil-secreting capsules. One week later, mice experienced 15-min of 2-vessel occlusion (2-VO) or sham surgical procedures. Five days later, mice were exposed to a fear conditioning protocol in which a specific context and novel tone were paired with mild footshock. Twenty-four hours following conditioning, contextual fear was assessed by measuring freezing behavior in the conditioned context (in the absence of the tone). This was followed by assessment of cue fear by measuring freezing behavior to the conditioned tone presented in a new context. When tested in the conditioned context, oil-treated mice that experienced 2-VO exhibited a significant reduction in freezing behavior whereas estradiol-treated mice that experienced 2-VO showed no disruption in freezing behavior. Freezing behavior when presented with the conditioned tone was unaffected by either surgery or hormone treatment. These findings suggest that global ischemia causes impairments in performance on the hippocampally-dependent contextual fear task but not conditioned cue-based fear. Furthermore, estradiol prevented the ischemia-induced impairment in contextual fear conditioning. Fluoro-Jade (FJ) staining revealed neuronal degeneration throughout the dorsal hippocampus of mice that experienced 2-VO. Estradiol treatment reduced the number of FJ+ cells in CA1 and CA2, but not in CA3 or in the dentate gyrus. Together, these findings suggest that 15 min of global ischemia causes extensive hippocampal neurodegeneration and disrupts contextual fear conditioning processes in mice and that estradiol protects against these adverse effects.
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Affiliation(s)
- Jennah L Durham
- Department of Psychology, Williams College, Williamstown, MA 01267, USA
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75
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Hernández-Fonseca K, Massieu L, García de la Cadena S, Guzmán C, Camacho-Arroyo I. Neuroprotective role of estradiol against neuronal death induced by glucose deprivation in cultured rat hippocampal neurons. Neuroendocrinology 2012; 96:41-50. [PMID: 22213775 DOI: 10.1159/000334229] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 10/08/2011] [Indexed: 12/22/2022]
Abstract
Studies have reported the protective effect of estradiol (E(2)) against neuronal death induced by several insults including oxygen deprivation, mitochondrial toxins and activation of glutamate receptors. Glucose deprivation (GD) is associated with ischemia and hypoglycemia, and to date there is no effective therapeutic agent able to prevent neuronal damage induced by these conditions. In this study, we have investigated the effects of 17β-E(2) and the selective agonists of the alpha (ERα) and beta (ERβ) estrogen receptors, propyl pyrazole triol (PPT) and diarylpropionitrile (DPN), respectively, on neuronal death induced by GD in cultured rat hippocampal neurons. We have also analyzed the expression of both ER isoforms after GD. Results show that GD for 2 and 4 h reduces cell survival by 42 and 55%, respectively. Treatment with 17β-E(2) (10 nM to 10 µM) induces a dose-dependent protective effect that is blocked by ICI 182,780, an ER antagonist, and by 1,3-bis(4-hydroxyphenyl)-4-methyl-5-[4-(-piperidinylethoxy)phenol]-1H'pyrazole dihydrochloride (MPP) and 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]phenol (PHTPP), selective ERα and ERβ antagonists, respectively. The ERα and ERβ agonists PPT and DPN show a similar neuroprotective effect to that of 17β-E(2), but DPN is more efficient. In addition, hippocampal neurons under normal conditions show a higher expression of the ERβ isoform. When exposed to GD during 4 h, the expression of both ER isoforms is increased, while only that of the ERβ isoform significantly increases after 2 h of GD. Results demonstrate that E(2) prevents neuronal death induced by GD through its interaction with ER, although the ERβ isoform might have a predominant role. Results also suggest that GD differentially alters the expression of ERα and ERβ in hippocampal neurons.
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76
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Irwin RW, Yao J, To J, Hamilton RT, Cadenas E, Brinton RD. Selective oestrogen receptor modulators differentially potentiate brain mitochondrial function. J Neuroendocrinol 2012; 24:236-48. [PMID: 22070562 PMCID: PMC3264398 DOI: 10.1111/j.1365-2826.2011.02251.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The mitochondrial energy-transducing capacity of the brain is important for long-term neurological health and is influenced by endocrine hormone responsiveness. The present study aimed to determine the role of oestrogen receptor (ER) subtypes in regulating mitochondrial function using selective agonists for ERα (propylpyrazoletriol; PPT) and ERβ (diarylpropionitrile; DPN). Ovariectomised female rats were treated with 17β-oestradiol (E(2) ), PPT, DPN or vehicle control. Both ER selective agonists significantly increased the mitochondrial respiratory control ratio and cytochrome oxidase (COX) activity relative to vehicle. Western blots of purified whole brain mitochondria detected ERα and, to a greater extent, ERβ localisation. Pre-treatment with DPN, an ERβ agonist, significantly increased ERβ association with mitochondria. In the hippocampus, DPN activated mitochondrial DNA-encoded COX I expression, whereas PPT was ineffective, indicating that mechanistically ERβ, and not ERα, activated mitochondrial transcriptional machinery. Both selective ER agonists increased protein expression of nuclear DNA-encoded COX IV, suggesting that activation of ERβ or ERα is sufficient. Selective ER agonists up-regulated a panel of bioenergetic enzymes and antioxidant defence proteins. Up-regulated proteins included pyruvate dehydrogenase, ATP synthase, manganese superoxide dismutase and peroxiredoxin V. In vitro, whole cell metabolism was assessed in live primary cultured hippocampal neurones and mixed glia. The results of analyses conducted in vitro were consistent with data obtained in vivo. Furthermore, lipid peroxides, accumulated as a result of hormone deprivation, were significantly reduced by E(2) , PPT and DPN. These findings suggest that the activation of both ERα and ERβ is differentially required to potentiate mitochondrial function in brain. As active components in hormone therapy, synthetically designed oestrogens as well as natural phyto-oestrogen cocktails can be tailored to improve brain mitochondrial endpoints.
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Affiliation(s)
- Ronald W. Irwin
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
| | - Jia Yao
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
| | - Jimmy To
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
| | - Ryan T. Hamilton
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
| | - Enrique Cadenas
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
| | - Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, Los Angeles, California, 90033
- Program in Neuroscience, University of Southern California, Los Angeles, California, 90033
- Address correspondence to: Roberta Diaz Brinton, Ph.D., Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Pharmaceutical Sciences Center, 1985 Zonal Avenue, Los Angeles, California, 90089, Tel. 323-442-1428; Fax. 323-442-1489;
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Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M. Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 153-8902 Japan
| | - Christian J. Pike
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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78
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Barron AM, Pike CJ. Sex hormones, aging, and Alzheimer's disease. Front Biosci (Elite Ed) 2012. [PMID: 22201929 DOI: 10.2741/434] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A promising strategy to delay and perhaps prevent Alzheimer's disease (AD) is to identify the age-related changes that put the brain at risk for the disease. A significant normal age change known to result in tissue-specific dysfunction is the depletion of sex hormones. In women, menopause results in a relatively rapid loss of estradiol and progesterone. In men, aging is associated with a comparatively gradual yet significant decrease in testosterone. We review a broad literature that indicates age-related losses of estrogens in women and testosterone in men are risk factors for AD. Both estrogens and androgens exert a wide range of protective actions that improve multiple aspects of neural health, suggesting that hormone therapies have the potential to combat AD pathogenesis. However, translation of experimental findings into effective therapies has proven challenging. One emerging treatment option is the development of novel hormone mimetics termed selective estrogen and androgen receptor modulators. Continued research of sex hormones and their roles in the aging brain is expected to yield valuable approaches to reducing the risk of AD.
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Affiliation(s)
- Anna M Barron
- USC Davis School of Gerontology, University of Southern California, Los Angeles, CA 90089 USA
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79
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Al Sweidi S, Sánchez MG, Bourque M, Morissette M, Dluzen D, Di Paolo T. Oestrogen receptors and signalling pathways: implications for neuroprotective effects of sex steroids in Parkinson's disease. J Neuroendocrinol 2012; 24:48-61. [PMID: 21790809 DOI: 10.1111/j.1365-2826.2011.02193.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Parkinson's disease (PD) is an age-related neurodegenerative disorder with a higher incidence in the male population. In the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD, 17β-oestradiol but not androgens were shown to protect dopamine (DA) neurones. We report that oestrogen receptors (ER)α and β distinctly contribute to neuroprotection against MPTP toxicity, as revealed by examining the membrane DA transporter (DAT), the vesicular monoamine transporter 2 (VMAT2) and tyrosine hyroxylase in ER wild-type (WT) and knockout (ERKO) C57Bl/6 male mice. Intact ERKOβ mice had lower levels of striatal DAT and VMAT2, whereas ERKOα mice were the most sensitive to MPTP toxicity compared to WT and ERKOβ mice and had the highest levels of plasma androgens. In both ERKO mice groups, treatment with 17β-oestradiol did not provide neuroprotection against MPTP, despite elevated plasma 17β-oestradiol levels. Next, the recently described membrane G protein-coupled oestrogen receptor (GPER1) was examined in female Macaca fascicularis monkeys and mice. GPER1 levels were increased in the caudate nucleus and the putamen of MPTP-monkeys and in the male mouse striatum lesioned with methamphetamine or MPTP. Moreover, neuroprotective mechanisms in response to oestrogens transmit via Akt/glycogen synthase kinase-3 (GSK3) signalling. The intact and lesioned striata of 17β-oestradiol treated monkeys, similar to that of mice, had increased levels of pAkt (Ser 473)/βIII-tubulin, pGSK3 (Ser 9)/βIII-tubulin and Akt/βIII-tubulin. Hence, ERα, ERβ and GPER1 activation by oestrogens is imperative in the modulation of ER signalling and serves as a basis for evaluating nigrostriatal neuroprotection.
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Affiliation(s)
- S Al Sweidi
- Molecular Endocrinology and Genomic Research Center, CHUQ (CHUL), Quebec City, Canada
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80
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Simpkins JW, Perez E, Wang X, Yang S, Wen Y, Singh M. The potential for estrogens in preventing Alzheimer's disease and vascular dementia. Ther Adv Neurol Disord 2011; 2:31-49. [PMID: 19890493 DOI: 10.1177/1756285608100427] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Estrogens are the best-studied class of drugs for potential use in the prevention of Alzheimer's disease (AD). These steroids have been shown to be potent neuroprotectants both in vitro and in vivo, and to exert effects that are consistent with their potential use in prevention of AD. These include the prevention of the processing of amyloid precursor protein (APP) into beta-amyloid (Aß), the reduction in tau hyperphosphorylation, and the elimination of catastrophic attempts at neuronal mitosis. Further, epidemiological data support the efficacy of early postmenopausal use of estrogens for the delay or prevention of AD. Collectively, this evidence supports the further development of estrogen-like compounds for prevention of AD. Several approaches to enhance brain specificity of estrogen action are now underway in an attempt to reduce the side effects of chronic estrogen therapy in AD.
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Affiliation(s)
- James W Simpkins
- Department of Pharmacology and Neuroscience, Institute for Aging and Alzheimer's Disease Research, Center FOR HER (Focused On Resources for her Health, Education and Research), University of North Texas Health Science Center, Fort Worth, TX, USA
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81
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Zhao L, Yao J, Mao Z, Chen S, Wang Y, Brinton RD. 17β-Estradiol regulates insulin-degrading enzyme expression via an ERβ/PI3-K pathway in hippocampus: relevance to Alzheimer's prevention. Neurobiol Aging 2011; 32:1949-63. [PMID: 20053478 PMCID: PMC2889185 DOI: 10.1016/j.neurobiolaging.2009.12.010] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 11/13/2009] [Accepted: 12/11/2009] [Indexed: 01/11/2023]
Abstract
Insulin-degrading enzyme (IDE), an enzyme that primarily degrades insulin, has recently been demonstrated to play a significant role in the catabolism of amyloid β (Aβ) protein in the brain. Reduced IDE expression and/or activity have been associated with the etiology and development of Alzheimer's disease (AD). Using three model systems, the present investigation provides the first documentation indicating that estrogen robustly regulates the expression of IDE in normal, menopausal and early-stage AD brains. In vitro analyses in primary cultures of rat hippocampal neurons revealed that 17β-estradiol (17β-E2) increased IDE in both mRNA and protein levels in a time-dependent manner. Further pharmacological analyses indicated that 17β-E2-induced IDE expression was dependent upon estrogen receptor (ER) β and required activation of phosphatidylinositol 3-kinase (PI3-K). In vivo analyses in adult female rats revealed a brain region-specific responsive profile. Ovariectomy (OVX) induced a significant decline in IDE expression in the hippocampus, which was prevented by 17β-E2. Neither OVX nor 17β-E2 affected IDE expression in the cerebellum. In vivo analyses in triple transgenic AD (3xTg-AD) female mice revealed an inverse correlation between the age-related increase in Aβ load and the decrease in IDE expression in the hippocampal formation. Treatment with 17β-E2 attenuated Aβ accumulation/plaque formation and elevated hippocampal IDE expression in 12-month-old 3xTg-AD OVX mice. Collectively, these findings indicate that 17β-E2 regulates IDE expression in a brain region-specific manner and such a regulatory role in the hippocampus, mediated by an ERβ/PI3-K pathway, could serve as a direct mechanism underlying estrogen-mediated preventative effect against AD when initiated at the onset of menopause.
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Affiliation(s)
- Liqin Zhao
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Jia Yao
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Zisu Mao
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Shuhua Chen
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Yan Wang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
| | - Roberta Diaz Brinton
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, United States
- Program in Neuroscience, University of Southern California, Los Angeles, CA 90033, United States
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82
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Smith YR, Bowen L, Love TM, Berent-Spillson A, Frey KA, Persad CC, Reame NK, Koeppe RA, Zubieta JK. Early initiation of hormone therapy in menopausal women is associated with increased hippocampal and posterior cingulate cholinergic activity. J Clin Endocrinol Metab 2011; 96:E1761-70. [PMID: 21865354 PMCID: PMC3205894 DOI: 10.1210/jc.2011-0351] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
CONTEXT The role of ovarian hormones in maintaining neuronal integrity and cognitive function is still debated. This study was undertaken to clarify the potential relationship between postmenopausal hormone use and the cholinergic system. OBJECTIVE We hypothesized that early initiated hormone therapy (HT) preserves the cholinergic system and that estrogen therapy (ET) would be associated with higher levels of acetylcholinesterase activity in the posterior cingulate cortex and hippocampus compared to estrogen plus progestin therapy (EPT) or no HT. DESIGN AND SETTING We conducted a cross-sectional study at a university teaching hospital. PATIENTS Fifty postmenopausal women (age, 65.2 ± 0.7 yr) with early long-term HT (n = 34; 13 ET and 21 EPT) or no HT (n = 16) participated in the study. INTERVENTIONS There were no interventions. MAIN OUTCOME MEASURE We measured cholinergic activity (acetylcholinesterase) in the hippocampus and posterior cingulate brain regions as measured by N-[(11)C]methylpiperidin-4-yl propionate and positron emission tomography as a marker of cholinergic function. RESULTS Significant effects of treatment on cholinergic activity measures were obtained in the left hippocampus (F = 3.56; P = 0.04), right hippocampus (F = 3.42; P = 0.04), and posterior cingulate (F = 3.76; P = 0.03). No significant effects were observed in a cortical control region. Post hoc testing identified greater cholinergic activity in the EPT group compared to the no-HT group in the left hippocampus (P = 0.048) and posterior cingulate (P = 0.045), with a nonstatistically significant trend in the right hippocampus (P = 0.073). CONCLUSIONS A differential effect of postmenopausal ET and EPT on cholinergic neuronal integrity was identified in postmenopausal women. The findings are consistent with a preservation of cholinergic neuronal integrity in the EPT group.
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Affiliation(s)
- Yolanda R Smith
- Department of Obstetrics and Gynecology, University of Michigan Health Systems, 1500 East Medical Center Drive, Room L4224 Women's Hospital, Ann Arbor, Michigan 48109-0276, USA.
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83
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Abstract
Newborn mammals are totally dependent on maternal milk and care for survival. The mother's brain undergoes different behavioural, physiological and emotional adaptations that make the mother more likely to satisfy the demands of the offspring. Recent reports from our group show that, compared to nulliparous rats, lactation diminishes cell damage induced by excitotoxicity in the dorsal hippocampus of the dam after systemic or i.c. administration of kainic acid (KA) and the resulting motor seizures. Elevated levels of prolactin (PRL), oxytocin, progesterone and glucocorticoids are characteristics of lactation, and the pronounced fluctuation of these hormones occurring in this phase may play a role protecting the hippocampus. Indeed, PRL administration to ovariectomised rats significantly diminishes the deleterious effects of KA in the dorsal hippocampus and reduces the progression of KA-induced seizures. Thus, lactation is a natural model for neuroprotection because it effectively prevents acute and chronic cell damage of the hippocampus induced by excitotoxicity.
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Affiliation(s)
- T Morales
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, México.
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84
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Etgen AM, Jover-Mengual T, Zukin RS. Neuroprotective actions of estradiol and novel estrogen analogs in ischemia: translational implications. Front Neuroendocrinol 2011; 32:336-52. [PMID: 21163293 PMCID: PMC3080451 DOI: 10.1016/j.yfrne.2010.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 12/06/2010] [Accepted: 12/09/2010] [Indexed: 11/15/2022]
Abstract
This review highlights our investigations into the neuroprotective efficacy of estradiol and other estrogenic agents in a clinically relevant animal model of transient global ischemia, which causes selective, delayed death of hippocampal CA1 neurons and associated cognitive deficits. We find that estradiol rescues a significant number of CA1 pyramidal neurons that would otherwise die in response to global ischemia, and this is true when hormone is provided as a long-term pretreatment at physiological doses or as an acute treatment at the time of reperfusion. In addition to enhancing neuronal survival, both forms of estradiol treatment induce measurable cognitive benefit in young animals. Moreover, estradiol and estrogen analogs that do not bind classical nuclear estrogen receptors retain their neuroprotective efficacy in middle-aged females deprived of ovarian hormones for a prolonged duration (8weeks). Thus, non-feminizing estrogens may represent a new therapeutic approach for treating the neuronal damage associated with global ischemia.
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Affiliation(s)
- Anne M Etgen
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA.
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85
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Caceres LG, Uran SL, Zorrilla Zubilete MA, Romero JI, Capani F, Guelman LR. An early treatment with 17-β-estradiol is neuroprotective against the long-term effects of neonatal ionizing radiation exposure. J Neurochem 2011; 118:626-35. [PMID: 21631508 DOI: 10.1111/j.1471-4159.2011.07334.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ionizing radiations can induce oxidative stress on target tissues, acting mainly through reactive oxygen species (ROS). The aim of this work was to investigate if 17-β-estradiol (βE) was able to prevent hippocampal-related behavioral and biochemical changes induced by neonatal ionizing radiation exposure and to elucidate a potential neuroprotective mechanism. Male Wistar rats were irradiated with 5 Gy of X-rays between 24 and 48 h after birth. A subset of rats was subcutaneously administered with successive injections of βE or 17-α-estradiol (αE), prior and after irradiation. Rats were subjected to different behavioral tasks to evaluate habituation and associative memory as well as anxiety levels. Hippocampal ROS levels and protein kinase C (PKC) activity were also assessed. Results show that although βE was unable to prevent radiation-induced hippocampal PKC activity changes, most behavioral abnormalities were reversed. Moreover, hippocampal ROS levels in βE-treated irradiated rats approached control values. In addition, αE administered to irradiated animals was effective in preventing radiation-induced alterations. In conclusion, βE was able to counteract behavioral and biochemical changes induced in irradiated animals, probably acting through an antioxidant mechanism.
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Affiliation(s)
- Lucila G Caceres
- 1ª Cátedra de Farmacología, Facultad de Medicina, UBA, CEFYBO-CONICET, Buenos Aires, Argentina
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86
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McDowell ML, Das A, Smith JA, Varma AK, Ray SK, Banik NL. Neuroprotective effects of genistein in VSC4.1 motoneurons exposed to activated microglial cytokines. Neurochem Int 2011; 59:175-84. [PMID: 21672594 DOI: 10.1016/j.neuint.2011.04.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 04/20/2011] [Accepted: 04/27/2011] [Indexed: 11/19/2022]
Abstract
Pro-inflammatory cytokines released from activated microglia may be responsible for neuronal damage and resulting motor deficits associated with CNS disorders such as spinal cord injury, Parkinson's disease, and multiple sclerosis. Estrogen (17β-estradiol) is capable of ameliorating motoneuron death following spinal cord injury, but has a number of deleterious side effects. Genistein (GEN), an estrogen receptor beta agonist and potent antioxidant, may represent an alternative to estrogen in treating neurodegenerative disorders. However, little is known about the neuroprotective effects of GEN. We therefore tested whether GEN would prevent apoptosis in cultured motoneurons following exposure to pro-inflammatory cytokines released from IFN-γ activated microglia. Exposure of ventral spinal cord 4.1 motoneurons to microglial cytokine supernatant in vitro caused significant apoptosis and reduced mitochondrial membrane potential. An increase in reactive oxygen species, intracellular Ca(2+), calpain, caspases, cytochrome c, and the bax:bcl-2 ratio were also noted. GEN treatment reversed apoptotic death and cellular changes following cytokine exposure and was associated with increased expression of estrogen receptor β suggesting that GEN may promote neuroprotection via receptor-mediated pathways. The addition of ICI 182, 780, an estrogen receptor antagonist following GEN treatment attenuated neuroprotection, suggesting that GEN may act mainly via estrogen receptor β to protect VSC4.1 motoneurons. We conclude that GEN protects cultured ventral spinal cord 4.1 cells from inflammatory insult and thus may represent a potential beneficial therapy in the treatment of neurodegenerative disorders.
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Affiliation(s)
- Misty L McDowell
- Department of Neurosciences, Division of Neurology, Medical University of South Carolina, 96 Jonathan Lucas St., 309 Clinical Sciences Building, Charleston, SC 29425, USA.
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87
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Abdelhamid R, Luo J, VandeVrede L, Kundu I, Michalsen B, Litosh VA, Schiefer IT, Gherezghiher T, Yao P, Qin Z, Thatcher GRJ. Benzothiophene Selective Estrogen Receptor Modulators Provide Neuroprotection by a novel GPR30-dependent Mechanism. ACS Chem Neurosci 2011; 2:256-268. [PMID: 21731800 PMCID: PMC3124785 DOI: 10.1021/cn100106a] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Accepted: 02/24/2011] [Indexed: 12/18/2022] Open
Abstract
The clinical benzothiophene SERM (BT-SERM), raloxifene, was compared with estrogens in protection of primary rat neurons against oxygen-glucose deprivation (OGD). Structure-activity relationships for neuroprotection were determined for a family of BT-SERMs displaying a spectrum of ERα and ERβ binding affinity and agonist/antagonist activity, leading to discovery of a neuroprotective pharmacophore, present in the clinically relevant SERMS, raloxifene and desmethylarzoxifene (DMA), for which submicromolar potency was observed for neuroprotection. BT-SERM neuroprotection did not correlate with binding to ER nor classical ER activity, however, both the neuroprotective SERMs and estrogens were shown, using pharmacological probes, to activate the same kinase signaling cascades. The antiestrogen ICI 182,780 inhibited the actions of estrogens, but not those of BT-SERMs, whereas antagonism of the G-protein coupled receptor, GPR30, was effective for both SERMs and estrogens. Since SERMs have antioxidant activity, ER-independent mechanisms were studied using the classical phenolic antioxidants, BHT and Trolox, and the Nrf2-dependent cytoprotective electrophile, sulforaphane. However, neuroprotection by these agents was not sensitive to GPR30 antagonism. Collectively, these data indicate that the activity of neuroprotective BT-SERMs is GPR30-dependent and ER-independent and not mediated by antioxidant effects. Comparison of novel BT-SERM derivatives and analogs identified a neuroprotective pharmacophore of potential use in design of novel neuroprotective agents with a spectrum of ER activity.
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Affiliation(s)
- Ramy Abdelhamid
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Jia Luo
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Lawren VandeVrede
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Indraneel Kundu
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Bradley Michalsen
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Vladislav A. Litosh
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Isaac T. Schiefer
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Teshome Gherezghiher
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Ping Yao
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Zhihui Qin
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
| | - Gregory R. J. Thatcher
- Department of Medicinal Chemistry and Pharmacognosy (M/C 781), College of Pharmacy, University of Illinois at Chicago, 833 South Wood Street, Chicago, Illinois 60612-7231, United States
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88
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Yao J, Chen S, Cadenas E, Brinton RD. Estrogen protection against mitochondrial toxin-induced cell death in hippocampal neurons: antagonism by progesterone. Brain Res 2011; 1379:2-10. [PMID: 21134358 PMCID: PMC3200366 DOI: 10.1016/j.brainres.2010.11.090] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 11/06/2010] [Accepted: 11/29/2010] [Indexed: 02/06/2023]
Abstract
Previously we demonstrated that mitochondrial dysfunction plays a critical role in the pathogenesis of Alzheimer's disease. Further, we have shown that the neuroprotective effects of 17β-estradiol (E2) are dependent upon mitochondrial function. In the current study, we sought to identify mitochondrial sites of E2 action that mediate neuroprotection by assessing the efficacy of E2 to protect neurons against inhibitors of mitochondrial respiration which target specific complexes within the respiratory chain. Subsequently, the impact of progesterone (P4) on E2-induced prevention against mitochondrial toxins was investigated. Mitochondrial inhibitors, rotenone, 3-NPA, antimycin, KCN, and oligomycin, exhibited concentration dependent toxicity in primary hippocampal neurons. The concentration inducing 30% cell death (LD30) was selected for analyses assessing the neuroprotective efficacy of ovarian hormones (E2 and P4). Pretreatment of hippocampal neurons with E2 significantly protected against 3-NPA (7.5mM) and antimycin (125 μM) induced cell death and was moderately neuroprotective against rotenone (3 μM). E2 was ineffective against KCN and oligomycin-induced cell death. Pretreatment with P4 was without effect against these mitochondrial inhibitors. Co-administration of P4 with E2 abolished E2 induced neuroprotection against 3-NPA and antimycin. Additional metabolic analyses indicated that E2 and P4 separately increased mitochondrial respiratory capacity whereas the co-administration of E2 and P4 resulted in diminished mitochondrial respiration. These findings indicate that E2 protects against mitochondrial toxins that target complexes I, II and III whereas P4 was without effect. The data also predict that continuous combined co-administration of estrogen and progesterone common to many hormone therapy regimens is unlikely to prevent the deficits in mitochondrial function.
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Affiliation(s)
- Jia Yao
- Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
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89
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Das A, Smith JA, Gibson C, Varma AK, Ray SK, Banik NL. Estrogen receptor agonists and estrogen attenuate TNF-α-induced apoptosis in VSC4.1 motoneurons. J Endocrinol 2011; 208:171-82. [PMID: 21068071 PMCID: PMC3951893 DOI: 10.1677/joe-10-0338] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Tumor necrosis factor-alpha (TNF-α) may cause apoptosis and inflammation in amyotrophic lateral sclerosis (ALS) and spinal cord injury (SCI). Recent studies suggest that estrogen (EST) provides neuroprotection against SCI. We tested whether 1,3,5-tris (4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) (EST receptor alpha (ERα) agonist), 2,3-bis (4-hydroxyphenyl) propionitrile (DPN) (EST receptor beta (ERβ) agonist), or EST itself would prevent apoptosis in VSC4.1 motoneurons following exposure to TNF-α. Cells were exposed to TNF-α and 15 min later treated with PPT, DPN, or EST. Posttreatment with 50 nM PPT, 50 nM DPN, or 150 nM EST prevented cell death in VSC4.1 motoneurons. Treatment of VSC4.1 motoneurons with PPT, DPN, or EST induced overexpression of ERα, ERβ, or both, which contributed to neuroprotection by upregulating expression of anti-apoptotic proteins (p-AKT, p-CREB, Bcl-2, and p-Src). Our analyses also revealed that EST agonists and EST increased phosphorylation of extracellular signal-regulated kinase (ERK). The L-type Ca(2+) channel inhibitor, nifedipine (10 μM), partially inhibited EST agonist and EST-induced increase in phosphorylated ERK expression. The mitogen-activated protein kinase inhibitor, PD98059 (5 μM), partially prevented ER agonists and EST from providing neuroprotection to TNF-α toxicity. Presence of the nuclear ER antagonist, ICI 182 780 (10 μM), blocked the neuroprotection provided by all three ER agonists tested. Taken together, our data indicate that both ERα and ERβ contribute to PPT, DPN, or EST-mediated neuroprotection with similar signaling profiles. Our data strongly imply that PPT, DPN, or EST can be used as effective neuroprotective agents to attenuate motoneuron death in ALS and SCI.
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Affiliation(s)
- Arabinda Das
- Department of Neurosciences, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, South Carolina 29425, USA
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90
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Abstract
Women are more susceptible to a variety of autoimmune diseases including systemic lupus erythematosus (SLE), multiple sclerosis (MS), primary biliary cirrhosis, rheumatoid arthritis and Hashimoto's thyroiditis. This increased susceptibility in females compared to males is also present in animal models of autoimmune diseases such as spontaneous SLE in (NZBxNZW)F1 and NZM.2328 mice, experimental autoimmune encephalomyelitis (EAE) in SJL mice, thyroiditis, Sjogren's syndrome in MRL/Mp-lpr/lpr mice and diabetes in non-obese diabetic mice. Indeed, being female confers a greater risk of developing these diseases than any single genetic or environmental risk factor discovered to date. Understanding how the state of being female so profoundly affects autoimmune disease susceptibility would accomplish two major goals. First, it would lead to an insight into the major pathways of disease pathogenesis and, secondly, it would likely lead to novel treatments which would disrupt such pathways.
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Affiliation(s)
- Rhonda Voskuhl
- Professor, UCLA Dept, of Neurology, Jack H Skirball Chair for Multiple Sclerosis Research, Director, UCLA Multiple Sclerosis Program, Neuroscience Research Building 1, Room 475D, 635 Charles Young Drive South, Los Angeles, CA 90095, USA.
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91
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Reply of the Authors. Fertil Steril 2011. [DOI: 10.1016/j.fertnstert.2010.09.048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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92
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Gingerich S, Kim G, Chalmers J, Koletar M, Wang X, Wang Y, Belsham D. Estrogen receptor alpha and G-protein coupled receptor 30 mediate the neuroprotective effects of 17β-estradiol in novel murine hippocampal cell models. Neuroscience 2010; 170:54-66. [DOI: 10.1016/j.neuroscience.2010.06.076] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Revised: 06/25/2010] [Accepted: 06/28/2010] [Indexed: 12/13/2022]
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93
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Kim JJ, Pae CU, Kim MR, Min JA, Kim KH, Lee CU, Lee C, Paik IH. Association between Estrogen Receptor Gene Polymorphisms and Depression in Post-Menopausal Women: A Preliminary Study. Psychiatry Investig 2010; 7:224-7. [PMID: 20927313 PMCID: PMC2947812 DOI: 10.4306/pi.2010.7.3.224] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 05/29/2010] [Accepted: 06/17/2010] [Indexed: 11/19/2022] Open
Abstract
Post-menopausal women experience variable biological and psychological changes. The effect of reduced levels of estrogen can effect on post-menopausal depression. Estrogen triggers physiological responses by binding to the estrogen receptor (ER). Two subtypes of ER, ERa and ERb are now known. We investigated the significance of ERa and ERb polymorphisms and post-menopasal depression in this study. Forty three women with post-menopausal depression and 63 post-menopausal women without depression as normal controls were recruited. Polymerase chain reaction-restriction fragment length polymorphism method was used to investigate genotypes of ERa and ERb polymorphisms. Genotypes of PvuII and XbaI polymorphism of ERa receptor were significantly different in patients with post-menopausal depression comparing with controls. Genotypes of ERb did not show association with post-menopausal depression. Our study showed that ERa receptor polymorphism had an association with depression in post-menopausal women. It suggests that investigation of ER genes and their functions might be important for understanding pathophysilogical mechanism of post-menopausal depression.
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Affiliation(s)
- Jung Jin Kim
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Chi Un Pae
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Mi Ran Kim
- Department of Gynecology, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Jung Ah Min
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Kyung Hee Kim
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Chang Uk Lee
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Chul Lee
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - In Ho Paik
- Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul St. Mary's Hospital, Seoul, Korea
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94
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Roles of estrogen receptors alpha and beta in sexually dimorphic neuroprotection against glutamate toxicity. Neuroscience 2010; 170:1261-9. [PMID: 20732393 DOI: 10.1016/j.neuroscience.2010.08.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 07/24/2010] [Accepted: 08/11/2010] [Indexed: 02/05/2023]
Abstract
Although most agree that 17β-estradiol is neuroprotective via a variety of mechanisms, less is known about the role that biological sex plays in receptor-mediated estradiol neuroprotection. To address this issue we isolated primary cortical neurons from rat pups sorted by sex and assessed the ability of estradiol to protect the neurons from death induced by glutamate. Five-minute pretreatment with 10-50 nM 17β-estradiol protected female but not male neurons from glutamate toxicity 24 h later. Both estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) are expressed in these cultures. Experiments using an ERα selective agonist or antagonist indicate that this receptor is important for neuroprotection in female cortical neurons. The ERβ selective agonist conveys a small degree of neuroprotection to both male and female cortical neurons. Interestingly, we found that 17α estradiol and the novel membrane estrogen receptor (mER) agonist STX, but not bovine serum albumin conjugated estradiol or the GPR30 agonist G1 were neuroprotective in both male and female neurons. Taken together these data highlight a role for ERα in sexually dimorphic neuroprotection.
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95
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Nadzialek S, Pigneur LM, Wéron B, Kestemont P. Bcl-2 and Caspase 3 mRNA levels in the testes of gudgeon, Gobio gobio, exposed to ethinylestradiol (EE2). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 98:304-310. [PMID: 20356636 DOI: 10.1016/j.aquatox.2010.02.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Revised: 02/19/2010] [Accepted: 02/23/2010] [Indexed: 05/29/2023]
Abstract
Apoptosis inhibition has been reported in the male reproductive tract of teleost fish exposed to 17beta-estrogen or estrogen-like compounds. In order to understand the molecular mechanisms of cell death inhibition, this study examined 2 genes involved in the apoptotic pathway, Bcl-2 and Caspase 3, an anti-apoptotic and a pro-apoptotic genes, respectively. Partial cDNA sequences of Bcl-2 and Caspase 3 were cloned from gudgeon (Gobio gobio), a common European cyprinid fish. To follow mRNA levels of Bcl-2 and Caspase 3 under xenoestrogen exposure, we first performed an in vitro experiment on fish testis exposed to the most potent xenoestrogen found in the environment, ethinylestradiol (EE2). We further studied mRNA expression of both genes in the testis of fish exposed to xenoestrogens in situ. In the in vitro experiment, fragments of gudgeon testis were exposed for 21 days to 10(-3), 10(-2), 10(-1), 1 and 10 microg/L of EE2, as well as to positive (10(-1) microg/L of E2) and ethanol control medium. Results showed a significant induction of Bcl-2 mRNA at 10(-1) microg/L (p<0.05). Surprisingly, Caspase 3, a cell death effector, displayed the same profile as observed for the anti-apoptotic gene Bcl-2. In the experiment on wild gudgeon exposed from birth to an estrogenic sewage treatment plant effluent, the mRNA expression of Bcl-2 and Caspase 3 in feminized fish (ovotestis) was not significantly different due to high variability of expression between individuals. At the current state of knowledge on spermatogenesis disruption in teleost fish, in vitro studies seem better adapted than in situ investigations to enlighten the molecular pathway of apoptosis inhibition in testis exposed to xenoestrogens.
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Affiliation(s)
- Stéphanie Nadzialek
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Lise-Marie Pigneur
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Benjamin Wéron
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Patrick Kestemont
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium.
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96
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Effects of 17beta-estradiol replacement on the apoptotic effects caused by ovariectomy in the rat hippocampus. Life Sci 2010; 86:832-8. [PMID: 20394757 DOI: 10.1016/j.lfs.2010.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 03/22/2010] [Accepted: 04/06/2010] [Indexed: 12/12/2022]
Abstract
AIMS The aim of the present study was to investigate the effects of different periods of ovariectomy and 17beta-estradiol replacement on apoptotic cell death and expression of members of the Bcl-2 family in the rat hippocampus. MAIN METHODS Hippocampi were obtained from rats in proestrus, ovariectomized (15 days, 21 days and 36 days), ovariectomized for 15 days and then treated with 17beta-estradiol for 7 or 21 days, and rats ovariectomized and immediately treated with 17beta-estradiol for 21 days. The expression of Bcl-2 and Bax and the number of apoptotic cells were determined. KEY FINDINGS Ovariectomy decreased Bcl-2 expression and increased Bax expression and the number of apoptotic cells. Replacement with 17beta-estradiol (21 days) throughout the post-ovariectomy period reduced the number of apoptotic cells to the control levels, and prevented the effects of ovariectomy on Bax expression, but only partially restored the Bcl-2 expression. After 15 days of ovariectomy, the replacement with 17beta-estradiol for 21 days, but not for 7 days, restored the Bcl-2 and Bax expression and the percentage of apoptotic cells to the levels found in the proestrus control. SIGNIFICANCE The present results show that a physiological concentration of 17beta-estradiol may help maintain long-term neuronal viability by regulating the expression of members of the Bcl-2 family. Even after a period of hormonal deprivation, treatment with 17beta-estradiol is able to restore the expression of Bax and Bcl-2 to control levels, but the duration of the treatment is a key factor to obtain the desired effect. These data provide new understanding into the mechanisms contributing to the neuroprotective action of estrogen.
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97
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Peng HY, Chen GD, Lai CY, Hsieh MC, Hsu HH, Wu HC, Lin TB. PI3K modulates estrogen-dependent facilitation of colon-to-urethra cross-organ reflex sensitization in ovariectomized female rats. J Neurochem 2010; 113:54-66. [DOI: 10.1111/j.1471-4159.2010.06577.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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98
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Cerciat M, Unkila M, Garcia-Segura LM, Arevalo MA. Selective estrogen receptor modulators decrease the production of interleukin-6 and interferon-gamma-inducible protein-10 by astrocytes exposed to inflammatory challenge in vitro. Glia 2010; 58:93-102. [PMID: 19533603 DOI: 10.1002/glia.20904] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Expression of proinflammatory molecules by glial cells is involved in the pathophysiological changes associated with chronic neurological diseases. Under pathological conditions, astrocytes release a number of proinflammatory molecules, such as interleukin-6 (IL-6) and interferon-gamma-inducible protein-10 (IP-10). The ovarian hormone estradiol exerts protective effects in the central nervous system that, at least in part, may be mediated by a reduction of local inflammation. This study was designed to assess whether estradiol affects the production of IL-6 and IP-10 by primary cultures of newborn mice astrocytes exposed to lipopolysaccharide (LPS), a bacterial endotoxin known to cause neuroinflammation. In addition, the possible anti-inflammatory effect of several selective estrogen receptor modulators (SERMs) was also assessed. LPS induced an increase in the expression of IL-6 and IP-10 mRNA levels in astrocytes and an increase in IL-6 and IP-10 protein levels in the culture medium. These effects of LPS were impaired by estradiol and by the four SERMs tested in our study: tamoxifen, raloxifene, ospemifene, and bazedoxifene. All SERMs tested showed a similar effect on IL-6 and IP-10 mRNA levels, but raloxifene and ospemifene were more effective than tamoxifen and bazedoxifene in reducing protein levels in LPS-treated cultures. Finally, we report that news SERMs, ospemifene and bazedoxifene, exert anti-inflammatory actions by a mechanism involving classical estrogen receptors and by the inhibition of LPS-induced NFkappaB p65 transactivation. The results suggest that estrogenic compounds may be candidates to counteract brain inflammation under neurodegenerative conditions by targeting the production and release of proinflammatory molecules by astrocytes.
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Affiliation(s)
- M Cerciat
- Instituto Cajal, CSIC, Madrid, Spain
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99
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Interactions of estradiol and insulin-like growth factor-I signalling in the nervous system: new advances. PROGRESS IN BRAIN RESEARCH 2010; 181:251-72. [PMID: 20478442 DOI: 10.1016/s0079-6123(08)81014-x] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Estradiol and insulin-like growth factor-I (IGF-I) interact in the brain to regulate a variety of developmental and neuroplastic events. Some of these interactions are involved in the control of hormonal homeostasis and reproduction. However, the interactions may also potentially impact on affection and cognition by the regulation of adult neurogenesis in the hippocampus and by promoting neuroprotection under neurodegenerative conditions. Recent studies suggest that the interaction of estradiol and IGF-I is also relevant for the control of cholesterol homeostasis in neural cells. The molecular mechanisms involved in the interaction of estradiol and IGF-I include the cross-regulation of the expression of estrogen and IGF-I receptors, the regulation of estrogen receptor-mediated transcription by IGF-I and the regulation of IGF-I receptor signalling by estradiol. Current investigations are evidencing the role exerted by key signalling molecules, such as glycogen synthase kinase 3 and beta-catenin, in the cross-talk of estrogen receptors and IGF-I receptors in neural cells.
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100
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Fan X, Xu H, Warner M, Gustafsson JÅ. ERβ in CNS: New Roles in Development and Function. PROGRESS IN BRAIN RESEARCH 2010; 181:233-50. [DOI: 10.1016/s0079-6123(08)81013-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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