1
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Appleman ML, Thomas JL, Weiss AR, Nilaver BI, Cervera-Juanes R, Kohama SG, Urbanski HF. Effect of hormone replacement therapy on amyloid beta (Aβ) plaque density in the rhesus macaque amygdala. Front Aging Neurosci 2024; 15:1326747. [PMID: 38274989 PMCID: PMC10808750 DOI: 10.3389/fnagi.2023.1326747] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 12/27/2023] [Indexed: 01/27/2024] Open
Abstract
Background Amyloid beta (Aβ) plaque density was examined in the amygdala of rhesus macaques, to elucidate the influence of age, diet and hormonal environment. Methods Luminex technology was used to measure cerebrospinal fluid (CSF) concentrations of Aβ40 and Aβ42 across three decades, while immunohistochemistry was used to examine Aβ plaque density in the amygdala. Results Aβ40 was found to be the predominant isoform of Aβ in the CSF, but neither Aβ40 or Aβ42 concentrations showed an age-related change, and the ratio of Aβ42 to Aβ40 showed only a marginal increase. Significantly fewer Aβ plaques were detected in the amygdala of old ovariectomized animals if they received estradiol HRT (p < 0.001); similar results were obtained regardless of whether they had been maintained on a regular monkey chow for ∼48 months or on a high-fat, high-sugar, Western-style diet for ∼30 months. Conclusion The results demonstrate that HRT involving estrogen can reduce Aβ plaque load in a cognitive brain region of aged non-human primates. The results from this translational animal model may therefore have clinical relevance to the treatment of AD in post-menopausal women, whether used alone, or as a supplement to current pharmacological and monoclonal antibody-based interventions.
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Affiliation(s)
- Maria-Luisa Appleman
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
| | - Jeremy L. Thomas
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
| | - Alison R. Weiss
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
| | - Benjamin I. Nilaver
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
| | - Rita Cervera-Juanes
- Department of Physiology and Pharmacology, Atrium Health Wake Forest Baptist Medical Center, Winston-Salem, NC, United States
| | - Steven G. Kohama
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research Center, Beaverton, OR, United States
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
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2
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Prokai L, Nguyen V, Urbanski HF. Effect of estradiol replacement on hippocampal concentrations of estrogens in aged rhesus macaques maintained on an obesogenic diet. Biochem Biophys Rep 2023; 35:101548. [PMID: 37745986 PMCID: PMC10511332 DOI: 10.1016/j.bbrep.2023.101548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/30/2023] [Accepted: 09/12/2023] [Indexed: 09/26/2023] Open
Abstract
Replacement involving estrogens has proven efficacy at treating a wide range of disorders that develop with menopause or after surgical removal of the ovaries. Here, we tested whether an estradiol (E2) replacement paradigm that recapitulates physiological E2 levels in the circulation also recapitulates physiological E2 levels within the hippocampus. E2 was delivered continuously to old ovariectomized (OVX) rhesus macaques, maintained on a high-fat, high-sugar Western-style diet (WSD) for ∼30 months, via subcutaneous implants; this resulted in physiological concentrations of both estrone (E1) and E2 in the circulation (determined by LC-MS/MS). Surprisingly, however, hippocampal concentrations of E2 were markedly (P < 0.01) higher than in ovary-intact animals maintained on a regular chow diet. The data suggest that E2 replacement paradigms that appear to recapitulate physiological E2 concentrations in the circulation may produce hyper-physiological E2 levels within some brain areas, especially when individuals are maintained on a WSD.
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Affiliation(s)
- Laszlo Prokai
- Department of Pharmacology & Neuroscience, University of North Texas Health Science Center at Fort Worth, TX, 76063, USA
| | - Vien Nguyen
- Department of Pharmacology & Neuroscience, University of North Texas Health Science Center at Fort Worth, TX, 76063, USA
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, 97006, USA
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, 97239, USA
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3
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Pletzer B, Winkler-Crepaz K, Hillerer K. Progesterone and contraceptive progestin actions on the brain: A systematic review of animal studies and comparison to human neuroimaging studies. Front Neuroendocrinol 2023; 69:101060. [PMID: 36758768 DOI: 10.1016/j.yfrne.2023.101060] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 01/25/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023]
Abstract
In this review we systematically summarize the effects of progesterone and synthetic progestins on neurogenesis, synaptogenesis, myelination and six neurotransmitter systems. Several parallels between progesterone and older generation progestin actions emerged, suggesting actions via progesterone receptors. However, existing results suggest a general lack of knowledge regarding the effects of currently used progestins in hormonal contraception regarding these cellular and molecular brain parameters. Human neuroimaging studies were reviewed with a focus on randomized placebo-controlled trials and cross-sectional studies controlling for progestin type. The prefrontal cortex, amygdala, salience network and hippocampus were identified as regions of interest for future preclinical studies. This review proposes a series of experiments to elucidate the cellular and molecular actions of contraceptive progestins in these areas and link these actions to behavioral markers of emotional and cognitive functioning. Emotional effects of contraceptive progestins appear to be related to 1) alterations in the serotonergic system, 2) direct/indirect modulations of inhibitory GABA-ergic signalling via effects on the allopregnanolone content of the brain, which differ between androgenic and anti-androgenic progestins. Cognitive effects of combined oral contraceptives appear to depend on the ethinylestradiol dose.
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Affiliation(s)
- Belinda Pletzer
- Department of Psychology & Centre for Cognitive Neuroscience, Paris-Lodron-University Salzburg, Salzburg Austria.
| | | | - Katharina Hillerer
- Department of Gynaecology & Obstetrics, Private Medical University, Salzburg, Austria
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4
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Zhou S, Xi Y, Chen Y, Fu F, Yan W, Li M, Wu Y, Luo A, Li Y, Wang S. Low WIP1 Expression Accelerates Ovarian Aging by Promoting Follicular Atresia and Primordial Follicle Activation. Cells 2022; 11:cells11233920. [PMID: 36497179 PMCID: PMC9736686 DOI: 10.3390/cells11233920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/20/2022] [Accepted: 11/28/2022] [Indexed: 12/07/2022] Open
Abstract
Our previous study demonstrated that ovarian wild-type P53-induced phosphatase 1 (WIP1) expression decreased with age. We hypothesized that WIP1 activity was related to ovarian aging. The role of WIP1 in regulating ovarian aging and its mechanisms remain to be elucidated. Adult female mice with or without WIP1 inhibitor (GSK2830371) treatment were divided into three groups (Veh, GSK-7.5, GSK-15) to evaluate the effect of WIP1 on ovarian endocrine and reproductive function and the ovarian reserve. In vitro follicle culture and primary granulosa cell culture were applied to explore the mechanisms of WIP1 in regulating follicular development. This study revealed that WIP1 expression in atretic follicle granulosa cells is significantly lower than that in healthy follicles. Inhibiting WIP1 phosphatase activity in mice induced irregular estrous cycles, caused fertility declines, and decreased the ovarian reserve through triggering excessive follicular atresia and primordial follicle activation. Primordial follicle depletion was accelerated via PI3K-AKT-rpS6 signaling pathway activation. In vitro follicle culture experiments revealed that inhibiting WIP1 activity impaired follicular development and oocyte quality. In vitro granulosa cell experiments further indicated that downregulating WIP1 expression promoted granulosa cell death via WIP1-p53-BAX signaling pathway-mediated apoptosis. These findings suggest that appropriate WIP1 expression is essential for healthy follicular development, and decreased WIP1 expression accelerates ovarian aging by promoting follicular atresia and primordial follicle activation.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ya Li
- Correspondence: (Y.L.); (S.W.); Tel.: +86-27-83663078 (Y.L. & S.W.)
| | - Shixuan Wang
- Correspondence: (Y.L.); (S.W.); Tel.: +86-27-83663078 (Y.L. & S.W.)
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5
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Kraynak M, Willging MM, Kuehlmann AL, Kapoor AA, Flowers MT, Colman RJ, Levine JE, Abbott DH. Aromatase Inhibition Eliminates Sexual Receptivity Without Enhancing Weight Gain in Ovariectomized Marmoset Monkeys. J Endocr Soc 2022; 6:bvac063. [PMID: 35592515 PMCID: PMC9113444 DOI: 10.1210/jendso/bvac063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Indexed: 11/19/2022] Open
Abstract
Context Ovarian estradiol supports female sexual behavior and metabolic function. While ovariectomy (OVX) in rodents abolishes sexual behavior and enables obesity, OVX in nonhuman primates decreases, but does not abolish, sexual behavior, and inconsistently alters weight gain. Objective We hypothesize that extra-ovarian estradiol provides key support for both functions, and to test this idea, we employed aromatase inhibition to eliminate extra-ovarian estradiol biosynthesis and diet-induced obesity to enhance weight gain. Methods Thirteen adult female marmosets were OVX and received (1) estradiol-containing capsules and daily oral treatments of vehicle (E2; n = 5); empty capsules and daily oral treatments of either (2) vehicle (VEH, 1 mL/kg, n = 4), or (3) letrozole (LET, 1 mg/kg, n = 4). Results After 7 months, we observed robust sexual receptivity in E2, intermediate frequencies in VEH, and virtually none in LET females (P = .04). By contrast, few rejections of male mounts were observed in E2, intermediate frequencies in VEH, and high frequencies in LET females (P = .04). Receptive head turns were consistently observed in E2, but not in VEH and LET females. LET females, alone, exhibited robust aggressive rejection of males. VEH and LET females demonstrated increased % body weight gain (P = .01). Relative estradiol levels in peripheral serum were E2 >>> VEH > LET, while those in hypothalamus ranked E2 = VEH > LET, confirming inhibition of local hypothalamic estradiol synthesis by letrozole. Conclusion Our findings provide the first evidence for extra-ovarian estradiol contributing to female sexual behavior in a nonhuman primate, and prompt speculation that extra-ovarian estradiol, and in particular neuroestrogens, may similarly regulate sexual motivation in other primates, including humans.
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Affiliation(s)
- Marissa Kraynak
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
- Endocrinology-Reproductive Physiology Training Program, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Molly M Willging
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
- Endocrinology-Reproductive Physiology Training Program, University of Wisconsin-Madison, Madison, WI 53715, USA
- Center for Women’s Health, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Alex L Kuehlmann
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Amita A Kapoor
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Matthew T Flowers
- Department of Medicine, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Ricki J Colman
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
- Endocrinology-Reproductive Physiology Training Program, University of Wisconsin-Madison, Madison, WI 53715, USA
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Jon E Levine
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
- Endocrinology-Reproductive Physiology Training Program, University of Wisconsin-Madison, Madison, WI 53715, USA
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - David H Abbott
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, WI 53715, USA
- Endocrinology-Reproductive Physiology Training Program, University of Wisconsin-Madison, Madison, WI 53715, USA
- Department of Obstetrics and Gynecology, University of Wisconsin-Madison, Madison, WI 53715, USA
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6
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Bustamante-Barrientos FA, Méndez-Ruette M, Ortloff A, Luz-Crawford P, Rivera FJ, Figueroa CD, Molina L, Bátiz LF. The Impact of Estrogen and Estrogen-Like Molecules in Neurogenesis and Neurodegeneration: Beneficial or Harmful? Front Cell Neurosci 2021; 15:636176. [PMID: 33762910 PMCID: PMC7984366 DOI: 10.3389/fncel.2021.636176] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/10/2021] [Indexed: 12/19/2022] Open
Abstract
Estrogens and estrogen-like molecules can modify the biology of several cell types. Estrogen receptors alpha (ERα) and beta (ERβ) belong to the so-called classical family of estrogen receptors, while the G protein-coupled estrogen receptor 1 (GPER-1) represents a non-classical estrogen receptor mainly located in the plasma membrane. As estrogen receptors are ubiquitously distributed, they can modulate cell proliferation, differentiation, and survival in several tissues and organs, including the central nervous system (CNS). Estrogens can exert neuroprotective roles by acting as anti-oxidants, promoting DNA repair, inducing the expression of growth factors, and modulating cerebral blood flow. Additionally, estrogen-dependent signaling pathways are involved in regulating the balance between proliferation and differentiation of neural stem/progenitor cells (NSPCs), thus influencing neurogenic processes. Since several estrogen-based therapies are used nowadays and estrogen-like molecules, including phytoestrogens and xenoestrogens, are omnipresent in our environment, estrogen-dependent changes in cell biology and tissue homeostasis have gained attention in human health and disease. This article provides a comprehensive literature review on the current knowledge of estrogen and estrogen-like molecules and their impact on cell survival and neurodegeneration, as well as their role in NSPCs proliferation/differentiation balance and neurogenesis.
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Affiliation(s)
- Felipe A Bustamante-Barrientos
- Immunology Program, Centro de Investigación e Innovación Biomédica (CiiB), Universidad de los Andes, Santiago, Chile.,Cells for Cells, Santiago, Chile
| | - Maxs Méndez-Ruette
- Neuroscience Program, Centro de Investigación e Innovación Biomédica (CiiB), Universidad de los Andes, Santiago, Chile
| | - Alexander Ortloff
- Departamento de Ciencias Veterinarias y Salud Pública, Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco, Chile
| | - Patricia Luz-Crawford
- Immunology Program, Centro de Investigación e Innovación Biomédica (CiiB), Universidad de los Andes, Santiago, Chile.,Facultad de Medicina, School of Medicine, Universidad de los Andes, Santiago, Chile
| | - Francisco J Rivera
- Laboratory of Stem Cells and Neuroregeneration, Faculty of Medicine, Institute of Anatomy, Histology and Pathology, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus Medical University, Salzburg, Austria
| | - Carlos D Figueroa
- Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Laboratory of Cellular Pathology, Institute of Anatomy, Histology and Pathology, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Luis Molina
- Facultad de Medicina y Ciencia, Universidad San Sebastián, Puerto Montt, Chile
| | - Luis Federico Bátiz
- Neuroscience Program, Centro de Investigación e Innovación Biomédica (CiiB), Universidad de los Andes, Santiago, Chile.,Facultad de Medicina, School of Medicine, Universidad de los Andes, Santiago, Chile
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7
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Gava G, Orsili I, Alvisi S, Mancini I, Seracchioli R, Meriggiola MC. Cognition, Mood and Sleep in Menopausal Transition: The Role of Menopause Hormone Therapy. MEDICINA (KAUNAS, LITHUANIA) 2019; 55:E668. [PMID: 31581598 PMCID: PMC6843314 DOI: 10.3390/medicina55100668] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 09/23/2019] [Accepted: 09/27/2019] [Indexed: 12/22/2022]
Abstract
During the menopausal transition, which begins four to six years before cessation of menses, middle-aged women experience a progressive change in ovarian activity and a physiologic deterioration of hypothalamic-pituitary-ovarian axis function associated with fluctuating hormone levels. During this transition, women can suffer symptoms related to menopause (such as hot flushes, sleep disturbance, mood changes, memory complaints and vaginal dryness). Neurological symptoms such as sleep disturbance, "brain fog" and mood changes are a major complaint of women transitioning menopause, with a significant impact on their quality of life, productivity and physical health. In this paper, we consider the associations between menopausal stage and/or hormone levels and sleep problems, mood and reduced cognitive performance. The role of estrogen and menopause hormone therapy (MHT) in cognitive function, sleep and mood are also discussed.
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Affiliation(s)
- Giulia Gava
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy.
| | - Isabella Orsili
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Stefania Alvisi
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Ilaria Mancini
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Renato Seracchioli
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Maria Cristina Meriggiola
- Gynecology and Physiopathology of Human Reproduction, S. Orsola-Malpighi Hospital, Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
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8
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Total Polysaccharides of Lily Bulb Ameliorate Menopause-Like Behavior in Ovariectomized Mice: Multiple Mechanisms Distinct from Estrogen Therapy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:6869350. [PMID: 31428228 PMCID: PMC6683782 DOI: 10.1155/2019/6869350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/21/2019] [Accepted: 06/27/2019] [Indexed: 12/28/2022]
Abstract
Our previous study has demonstrated the effects of aqueous extract of lily bulb in alleviating menopause-related psychiatric symptoms in ovariectomized (OVX) mice. This study sought to further investigate the psychotropic effects of total polysaccharides of lily bulb (TPLB) against anxiety, depression, and cognitive deterioration and the underlying mechanisms in OVX mice using behavioral, neurochemical, molecular, and proteomic approaches in comparison with estrogen therapy. While TPLB and estradiol showed similar effects in reducing OVX-induced anxiety, depression, and cognitive impairment, the psychotropic effects of TPLB were more closely associated with the predominant activation of estrogen receptors (ERs) and regulation of brain regional neurotransmitters and neurotrophins with minor effects on the uterus. Estradiol had similar potencies in binding affinity at ERα and ERβ, which caused widespread genetic and epigenetic effects. In contrast, TPLB displayed a higher affinity at ERβ than ERα, triggering the specific Ras/Akt/ERK/CREB signaling pathway without affecting any epigenetic activity. TPLB additionally modulated multiple proteins associated with mitochondrial oxidative stress, but estradiol did not. These results indicate that TPLB has comparable efficacy in reducing menopause-associated neuropsychological symptoms with a better safety profile compared to estrogen therapy. We suggest that TPLB could serve as a novel agent for menopause syndrome.
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9
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Lejri I, Grimm A, Eckert A. Mitochondria, Estrogen and Female Brain Aging. Front Aging Neurosci 2018; 10:124. [PMID: 29755342 PMCID: PMC5934418 DOI: 10.3389/fnagi.2018.00124] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 04/11/2018] [Indexed: 12/11/2022] Open
Abstract
Mitochondria play an essential role in the generation of steroid hormones including the female sex hormones. These hormones are, in turn, able to modulate mitochondrial activities. Mitochondria possess crucial roles in cell maintenance, survival and well-being, because they are the main source of energy as well as of reactive oxygen species (ROS) within the cell. The impairment of these important organelles is one of the central features of aging. In women’s health, estrogen plays an important role during adulthood not only in the estrous cycle, but also in the brain via neuroprotective, neurotrophic and antioxidant modes of action. The hypestrogenic state in the peri- as well as in the prolonged postmenopause might increase the vulnerability of elderly women to brain degeneration and age-related pathologies. However, the underlying mechanisms that affect these processes are not well elucidated. Understanding the relationship between estrogen and mitochondria might therefore provide better insights into the female aging process. Thus, in this review, we first describe mitochondrial dysfunction in the aging brain. Second, we discuss the estrogen-dependent actions on the mitochondrial activity, including recent evidence of the estrogen—brain-derived neurotrophic factor and estrogen—sirtuin 3 (SIRT3) pathways, as well as their potential implications during female aging.
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Affiliation(s)
- Imane Lejri
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
| | - Amandine Grimm
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
| | - Anne Eckert
- Neurobiology Lab for Brain Aging and Mental Health, Transfaculty Research Platform Molecular and Cognitive Neuroscience, University of Basel, Basel, Switzerland.,Psychiatric University Clinics, University of Basel, Basel, Switzerland
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10
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Zárate S, Stevnsner T, Gredilla R. Role of Estrogen and Other Sex Hormones in Brain Aging. Neuroprotection and DNA Repair. Front Aging Neurosci 2018. [PMID: 29311911 DOI: 10.3389/fnagi.2017.00430/xml/nlm] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023] Open
Abstract
Aging is an inevitable biological process characterized by a progressive decline in physiological function and increased susceptibility to disease. The detrimental effects of aging are observed in all tissues, the brain being the most important one due to its main role in the homeostasis of the organism. As our knowledge about the underlying mechanisms of brain aging increases, potential approaches to preserve brain function rise significantly. Accumulating evidence suggests that loss of genomic maintenance may contribute to aging, especially in the central nervous system (CNS) owing to its low DNA repair capacity. Sex hormones, particularly estrogens, possess potent antioxidant properties and play important roles in maintaining normal reproductive and non-reproductive functions. They exert neuroprotective actions and their loss during aging and natural or surgical menopause is associated with mitochondrial dysfunction, neuroinflammation, synaptic decline, cognitive impairment and increased risk of age-related disorders. Moreover, loss of sex hormones has been suggested to promote an accelerated aging phenotype eventually leading to the development of brain hypometabolism, a feature often observed in menopausal women and prodromal Alzheimer's disease (AD). Although data on the relation between sex hormones and DNA repair mechanisms in the brain is still limited, various investigations have linked sex hormone levels with different DNA repair enzymes. Here, we review estrogen anti-aging and neuroprotective mechanisms, which are currently an area of intense study, together with the effect they may have on the DNA repair capacity in the brain.
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Affiliation(s)
- Sandra Zárate
- Instituto de Investigaciones Biomédicas (INBIOMED, UBA-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina.,Departamento de Histología, Embriología, Biología Celular y Genética, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Tinna Stevnsner
- Danish Center for Molecular Gerontology and Danish Aging Research Center, Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
| | - Ricardo Gredilla
- Department of Physiology, Faculty of Medicine, Complutense University, Madrid, Spain
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11
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Zárate S, Stevnsner T, Gredilla R. Role of Estrogen and Other Sex Hormones in Brain Aging. Neuroprotection and DNA Repair. Front Aging Neurosci 2017; 9:430. [PMID: 29311911 PMCID: PMC5743731 DOI: 10.3389/fnagi.2017.00430] [Citation(s) in RCA: 159] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 12/14/2017] [Indexed: 12/13/2022] Open
Abstract
Aging is an inevitable biological process characterized by a progressive decline in physiological function and increased susceptibility to disease. The detrimental effects of aging are observed in all tissues, the brain being the most important one due to its main role in the homeostasis of the organism. As our knowledge about the underlying mechanisms of brain aging increases, potential approaches to preserve brain function rise significantly. Accumulating evidence suggests that loss of genomic maintenance may contribute to aging, especially in the central nervous system (CNS) owing to its low DNA repair capacity. Sex hormones, particularly estrogens, possess potent antioxidant properties and play important roles in maintaining normal reproductive and non-reproductive functions. They exert neuroprotective actions and their loss during aging and natural or surgical menopause is associated with mitochondrial dysfunction, neuroinflammation, synaptic decline, cognitive impairment and increased risk of age-related disorders. Moreover, loss of sex hormones has been suggested to promote an accelerated aging phenotype eventually leading to the development of brain hypometabolism, a feature often observed in menopausal women and prodromal Alzheimer's disease (AD). Although data on the relation between sex hormones and DNA repair mechanisms in the brain is still limited, various investigations have linked sex hormone levels with different DNA repair enzymes. Here, we review estrogen anti-aging and neuroprotective mechanisms, which are currently an area of intense study, together with the effect they may have on the DNA repair capacity in the brain.
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Affiliation(s)
- Sandra Zárate
- Instituto de Investigaciones Biomédicas (INBIOMED, UBA-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
- Departamento de Histología, Embriología, Biología Celular y Genética, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Tinna Stevnsner
- Danish Center for Molecular Gerontology and Danish Aging Research Center, Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
| | - Ricardo Gredilla
- Department of Physiology, Faculty of Medicine, Complutense University, Madrid, Spain
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12
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Stouffer RL, Woodruff TK. Nonhuman Primates: A Vital Model for Basic and Applied Research on Female Reproduction, Prenatal Development, and Women's Health. ILAR J 2017; 58:281-294. [PMID: 28985318 PMCID: PMC5886348 DOI: 10.1093/ilar/ilx027] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 06/30/2017] [Indexed: 12/20/2022] Open
Abstract
The comparative biology of reproduction and development in mammalian species is remarkable. Hence, because of similarities in environmental and neuroendocrine control of the reproductive axis, the cyclic function of the ovary and reproductive tract, establishment and control of the maternal-fetal-placental unit during pregnancy, and reproductive aging from puberty through menopause, nonhuman primates (NHPs) are valuable models for research related to women's reproductive health and its disorders. This chapter provides examples of research over the past 10+ years using Old World monkeys (notably macaque species), baboons, and to a lesser extent New World monkeys (especially marmosets) that contributed to our understanding of the etiology and therapies or prevention of: (1) ovarian disorders, e.g., polycystic ovary syndrome, mitochondrial DNA-based diseases from the oocyte; (2) uterine disorders, for example, endometriosis and uterine transplantation; and (3) pregnancy disorders, for example, preterm labor and delivery, environmental factors. Also, emerging opportunities such as viral (e.g., Zika) induced fetal defects and germline genomic editing to generate valuable primate models of human diseases (e.g., Huntington and muscular dystrophy) are addressed. Although the high costs, specialized resources, and ethical debate challenge the use of primates in biomedical research, their inclusion in fertility and infertility research is vital for continued improvements in women's reproductive health.
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Affiliation(s)
- Richard L Stouffer
- Richard L. Stouffer, Ph.D., is Professor in the Division of Reproductive and Developmental Sciences at the Oregon National Primate Research Center in Beaverton, Oregon and Professor in the Department of Obstetrics and Gynecology at Oregon Health & Sciences University in Portland, Oregon. Teresa K. Woodruff, Ph.D., is Thomas J. Watkins Professor of Obstetrics and Gynecology, Vice Chair of Research (OB/GYN), and Chief of the Division of Reproductive Science in Medicine at the Feinberg School of Medicine, and Professor of Molecular Biosciences at Weinberg College of Arts and Sciences, Northwestern University in Chicago, Illinois.
| | - Teresa K Woodruff
- Richard L. Stouffer, Ph.D., is Professor in the Division of Reproductive and Developmental Sciences at the Oregon National Primate Research Center in Beaverton, Oregon and Professor in the Department of Obstetrics and Gynecology at Oregon Health & Sciences University in Portland, Oregon. Teresa K. Woodruff, Ph.D., is Thomas J. Watkins Professor of Obstetrics and Gynecology, Vice Chair of Research (OB/GYN), and Chief of the Division of Reproductive Science in Medicine at the Feinberg School of Medicine, and Professor of Molecular Biosciences at Weinberg College of Arts and Sciences, Northwestern University in Chicago, Illinois.
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Honing in on hormone-sensitive neural targets for therapeutic intervention: mission impossible? Future Sci OA 2017. [DOI: 10.4155/fsoa-2017-0060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Banin RM, de Andrade IS, Cerutti SM, Oyama LM, Telles MM, Ribeiro EB. Ginkgo biloba Extract (GbE) Stimulates the Hypothalamic Serotonergic System and Attenuates Obesity in Ovariectomized Rats. Front Pharmacol 2017; 8:605. [PMID: 28928661 PMCID: PMC5591947 DOI: 10.3389/fphar.2017.00605] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 08/21/2017] [Indexed: 11/13/2022] Open
Abstract
Menopause is associated with increased risk to develop obesity but the mechanisms involved are not fully understood. We have shown that Ginkgo biloba extract (GbE) improved diet-induced obesity. Since GbE might be effective in the treatment of obesity related to menopause, avoiding the side effects of hormone replacement therapy, we investigated the effect of GbE on hypothalamic systems controlling energy homeostasis. Wistar rats were either ovariectomized (OVX) or Sham-operated. After 2 months, either 500 mg.kg-1 of GbE or vehicle were administered daily by gavage for 14 days. A subset of animals received an intracerebroventricular (i.c.v.) injection of serotonin (300 μg) or vehicle and food intake was measured after 12 and 24 h. Another subset was submitted to in vivo microdialysis and 5-HT levels of the medial hypothalamus were measured by high performance liquid chromatography, before and up to 2 h after the administration of 500 mg.kg-1 of GbE. Additional animals were used for quantification of 5-HT1A, 5-HT1B, 5-HT2C, 5-HTT, and pro-opiomelanocortin hypothalamic protein levels by Western blotting. OVX increased food intake and body weight and adiposity while GbE attenuated these alterations. i.c.v. serotonin significantly reduced food intake in Sham, Sham + GbE, and OVX + GbE groups while it failed to do so in the OVX group. In the OVX rats, GbE stimulated 5-HT microdialysate levels while it reduced hypothalamic 5-HTT protein levels. The results indicate that GbE improved the ovariectomy-induced resistance to serotonin hypophagia, at least in part through stimulation of the hypothalamic serotonergic activity. Since body weight gain is one of the most important consequences of menopause, the stimulation of the serotonergic transmission by GbE may represent a potential alternative therapy for menopause-related obesity.
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Affiliation(s)
- Renata M Banin
- Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São PauloSão Paulo, Brazil.,Setor de Morfofisiologia e Patologia, Departamento de Ciências Biológicas, Universidade Federal de São PauloDiadema, Brazil
| | - Iracema S de Andrade
- Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São PauloSão Paulo, Brazil
| | - Suzete M Cerutti
- Setor de Morfofisiologia e Patologia, Departamento de Ciências Biológicas, Universidade Federal de São PauloDiadema, Brazil
| | - Lila M Oyama
- Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São PauloSão Paulo, Brazil
| | - Mônica M Telles
- Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São PauloSão Paulo, Brazil.,Setor de Morfofisiologia e Patologia, Departamento de Ciências Biológicas, Universidade Federal de São PauloDiadema, Brazil
| | - Eliane B Ribeiro
- Disciplina de Fisiologia da Nutrição, Departamento de Fisiologia, Universidade Federal de São PauloSão Paulo, Brazil
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Novel oestrogen receptor β-selective ligand reduces obesity and depressive-like behaviour in ovariectomized mice. Sci Rep 2017; 7:4663. [PMID: 28680060 PMCID: PMC5498485 DOI: 10.1038/s41598-017-04946-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 06/07/2017] [Indexed: 12/11/2022] Open
Abstract
Hormonal changes due to menopause can cause various health problems including weight gain and depressive symptoms. Multiple lines of evidence indicate that oestrogen receptors (ERs) play a major role in postmenopausal obesity and depression. However, little is known regarding the ER subtype-specific effects on obesity and depressive symptoms. To delineate potential effects of ERβ activation in postmenopausal women, we investigated the effects of a novel oestrogen receptor β-selective ligand (C-1) in ovariectomized mice. Uterine weight, depressive behaviour, and weight gain were examined in sham-operated control mice and ovariectomized mice administered placebo, C-1, or 17β-oestradiol (E2). Administration of C-1 or E2 reduced body weight gain and depressive-like behaviour in ovariectomized mice, as assessed by the forced swim test. In addition, administration of E2 to ovariectomized mice increased uterine weight, but administration of C-1 did not result in a significant increase in uterine weight. These results suggest that the selective activation of ERβ in ovariectomized mice may have protective effects against obesity and depressive-like behaviour without causing an increase in uterine weight. The present findings raise the possibility of the application of ERβ-ligands such as C-1 as a novel treatment for obesity and depression in postmenopausal women.
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Bethea CL, Mueller K, Reddy AP, Kohama SG, Urbanski HF. Effects of obesogenic diet and estradiol on dorsal raphe gene expression in old female macaques. PLoS One 2017; 12:e0178788. [PMID: 28628658 PMCID: PMC5476244 DOI: 10.1371/journal.pone.0178788] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/18/2017] [Indexed: 12/19/2022] Open
Abstract
The beneficial effects of bioidentical ovarian steroid hormone therapy (HT) during the perimenopause are gaining recognition. However, the positive effects of estrogen (E) plus or minus progesterone (P) administration to ovariectomized (Ovx) lab animals were recognized in multiple systems for years before clinical trials could adequately duplicate the results. Moreover, very large numbers of women are often needed to find statistically significant results in clinical trials of HT; and there are still opposing results being published, especially in neural and cardiovascular systems. One of the obvious differences between human and animal studies is diet. Laboratory animals are fed a diet that is low in fat and refined sugar, but high in micronutrients. In the US, a large portion of the population eats what is known as a "western style diet" or WSD that provides calories from 36% fat, 44% carbohydrates (includes 18.5% sugars) and 18% protein. Unfortunately, obesity and diabetes have reached epidemic proportions and the percentage of obese women in clinical trials may be overlooked. We questioned whether WSD and obesity could decrease the positive neural effects of estradiol (E) in the serotonin system of old macaques that were surgically menopausal. Old ovo-hysterectomized female monkeys were fed WSD for 2.5 years, and treated with placebo, Immediate E (ImE) or Delayed E (DE). Compared to old Ovx macaques on primate chow and treated with placebo or E, the WSD-fed monkeys exhibited greater individual variance and blunted responses to E-treatment in the expression of genes related to serotonin neurotransmission, CRH components in the midbrain, synapse assembly, DNA repair, protein folding, ubiquitylation, transport and neurodegeneration. For many of the genes examined, transcript abundance was lower in WSD-fed than chow-fed monkeys. In summary, an obesogenic diet for 2.5 years in old surgically menopausal macaques blunted or increased variability in E-induced gene expression in the dorsal raphe. These results suggest that with regard to function and viability in the dorsal raphe, HT may not be as beneficial for obese women as normal weight women.
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Affiliation(s)
- Cynthia L. Bethea
- Division of Reproductive and Developmental Science, Oregon National Primate Research Center, Beaverton, OR, United States of America
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States of America
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, OR, United States of America
| | - Kevin Mueller
- Division of Reproductive and Developmental Science, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Arubala P. Reddy
- Department of Internal Medicine, Texas Technical University Health Sciences Center School of Medicine, Lubbock, TX, United States of America
| | - Steven G. Kohama
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States of America
| | - Henryk F. Urbanski
- Division of Neuroscience, Oregon National Primate Research Center, Beaverton, OR, United States of America
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, United States of America
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Holschbach MA, Lonstein JS. Motherhood and infant contact regulate neuroplasticity in the serotonergic midbrain dorsal raphe. Psychoneuroendocrinology 2017; 76:97-106. [PMID: 27898359 PMCID: PMC5272870 DOI: 10.1016/j.psyneuen.2016.10.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 10/03/2016] [Accepted: 10/25/2016] [Indexed: 12/22/2022]
Abstract
The adult brain shows remarkable neuroplasticity in response to hormones and the socioemotional modifications that they influence. In females with reproductive and maternal experience, this neuroplasticity includes the birth and death of cells in several forebrain regions involved in maternal caregiving and postpartum affective state. Such plasticity in midbrain sites critical for these behavioral and emotional processes has never been examined, though. By visualizing bromodeoxyuridine (BrdU) to label mitotic cells, NeuroD for neuronal precursors, and TUNEL to identify dying cells, we found that the midbrain dorsal raphe nucleus (DR, the source of most ascending serotoninergic projections) exhibited significant neuroplasticity in response to motherhood. Specifically, BrdU analyses revealed that DR newborn cell survival (but not proliferation) was regulated by reproductive state, such that cells born early postpartum were less likely to survive 12 days to reach the late postpartum period compared to cells born during late pregnancy that survived 12 days to reach the early postpartum period. Many of the surviving cells in the DR were NeuN immunoreactive, suggesting a neuronal phenotype. Consistent with these findings, late postpartum rats had fewer NeuroD-immunoreactive DR cells than early postpartum rats. Maternal experience contributed to the late postpartum reduction in DR newborn cell survival because removing the litter at parturition increased cell survival as well as reduced cell death. Unlike cytogenesis in the maternal hippocampus, which is reduced by circulating glucocorticoids, DR newborn cell survival was unaffected by postpartum adrenalectomy. These effects of reproductive state and motherhood on DR plasticity were associated with concurrent changes in DR levels of serotonin's precursor, 5-HTP, and its metabolite, 5-HIAA. Our results demonstrate for the first time that cytogenesis occurs in the midbrain DR of any adult mammal, that DR plasticity is influenced by female reproductive state and maternal experience, and that this plasticity is accompanied by changes in DR serotonergic function. Because serotonin is critical for postpartum caregiving behaviors and maternal affective state, plasticity in the DR may contribute to the neurochemical changes necessary for successful motherhood.
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Affiliation(s)
- M Allie Holschbach
- Neuroscience Program, 108 Giltner Hall, Michigan State University, East Lansing, MI 48824, USA.
| | - Joseph S Lonstein
- Neuroscience Program, 108 Giltner Hall, Michigan State University, East Lansing, MI 48824, USA
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Bethea CL, Reddy AP, Christian FL. How Studies of the Serotonin System in Macaque Models of Menopause Relate to Alzheimer's Disease1. J Alzheimers Dis 2017; 57:1001-1015. [PMID: 27662311 PMCID: PMC5575917 DOI: 10.3233/jad-160601] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Serotonin plays a key role in mood or affect, and dysfunction of the serotonin system has been linked to depression in humans and animal models. Depression appears prior to or coincident with overt symptoms of Alzheimer's disease (AD) in about 50% of patients, and some experts consider it a risk factor for the development of AD. In addition, AD is more prevalent in women, who also show increased incidence of depression. Indeed, it has been proposed that mechanisms underlying depression overlap the mechanisms thought to hasten AD. Women undergo ovarian failure and cessation of ovarian steroid production in middle age and the postmenopausal period correlates with an increase in the onset of depression and AD. This laboratory has examined the many actions of ovarian steroids in the serotonin system of non-human primates using a rhesus macaque model of surgical menopause with short or long-term estradiol (E) or estradiol plus progesterone (E+P) replacement therapy. In this mini-review, we present a brief synopsis of the relevant literature concerning AD, depression, and serotonin. We also present some of our data on serotonin neuron viability, the involvement of the caspase-independent pathway, and apoptosis-inducing factor in serotonin-neuron viability, as well as gene expression related to neurodegeneration and neuron viability in serotonin neurons from adult and aged surgical menopausal macaques. We show that ovarian steroids, particularly E, are crucial for serotonin neuron function and health. In the absence of E, serotonin neurons are endangered and deteriorating toward apoptosis. The possibility that this scenario may proceed or accompany AD in postmenopausal women seems likely.
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Affiliation(s)
- Cynthia L Bethea
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Beaverton, OR 97229 and Department of Obstetrics and Gynecology, Oregon Health and Sciences University, Portland, OR 97239
| | - Arubala P Reddy
- Department of Internal Medicine, Texas Tech Health Science Center, Lubbock, Texas 79430
| | - Fernanda Lima Christian
- Federal University of Santa Catarina, Center of Biological Sciences, Department of Physiological Sciences, Florianópolis, SC - Brazil 88040-900
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Wang W, Cui G, Jin B, Wang K, Chen X, Sun Y, Qin L, Bai W. Estradiol Valerate and Remifemin ameliorate ovariectomy-induced decrease in a serotonin dorsal raphe-preoptic hypothalamus pathway in rats. Ann Anat 2016; 208:31-39. [PMID: 27562857 DOI: 10.1016/j.aanat.2016.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 07/12/2016] [Accepted: 08/03/2016] [Indexed: 12/24/2022]
Abstract
Perimenopausal syndromes begin as ovarian function ceases and the most common symptoms are hot flushes. Data indicate that the projections of serotonin to hypothalamus may be involved in the mechanism of hot flushes. Therefore, the aim of this study is to investigate the potential role of the serotonin dorsal raphe-preoptic hypothalamus pathway for hot flushes in an animal model of menopause. We determined the changes in serotonin expression in the dorsal raphe (DR) and preoptic anterior hypothalamus (POAH) in ovariectomized rats. We also explored the therapeutical effects of estradiol valerate and Remifemin in this model. Eighty female Sprague-Dawley rats were randomly assigned to sham-operated (SHAM) group, ovariectomy (OVX) group with vehicle, ovariectomy with estradiol valerate treatment (OVX+E) group and ovariectomy with Remifemin (OVX+ICR) group. Serotonin expression was evaluated in the DR and POAH using immunofluorescence and quantified in the DR using an enzyme-linked immunosorbent assay (ELISA). Apoptosis was analyzed in the DR by TUNEL assay. The number of serotonin immunoreactive neurons and the level of serotonin expression in the DR decreased significantly following OVX compared to the SHAM group. No TUNEL-positive cells were detected in the DR in any group. In addition, following OVX, the number of serotonin-positive fibers decreased significantly in the ventromedial preoptic nucleus (VMPO), especially in the ventrolateral preoptic nucleus (VLPO). Treatment with either estradiol or Remifemin for 4 weeks countered the OVX-induced decreases in serotonin levels in both the DR and the hypothalamus, with levels in the treated rats similar to those in the SHAM group. A fluorescently labeled retrograde tracer was injected into the VLPO at the 4-week time point. A significantly lower percentage of serotonin with CTB double-labeled neurons in CTB-labeled neurons was demonstrated after ovariectomy, and both estradiol and Remifemin countered this OVX-induced decrease. We conclude that serotonin pathway is changed after ovariectomy, including the serotonin synthesis in DR and serotonin fibers in PO/AH, both E and Remifemin have an equivalent therapeutic effect on it.
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Affiliation(s)
- Wenjuan Wang
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Guangxia Cui
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China; Obstetrics and Gynecology Department, Civil Aviation General Hospital, No. 1 Gaojingjia Street, Chaoyang District, Beijing, China
| | - Biao Jin
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Ke Wang
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Xing Chen
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China
| | - Yu Sun
- Department of Obstetrics and Gynecology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China
| | - Lihua Qin
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
| | - Wenpei Bai
- Department of Obstetrics and Gynecology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China; Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China.
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