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van Melis LVJ, Peerdeman AM, González CA, van Kleef RGDM, Wopken JP, Westerink RHS. Effects of chronic insecticide exposure on neuronal network development in vitro in rat cortical cultures. Arch Toxicol 2024:10.1007/s00204-024-03840-0. [PMID: 39162819 DOI: 10.1007/s00204-024-03840-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Accepted: 08/08/2024] [Indexed: 08/21/2024]
Abstract
Developmental exposure to carbamates, organophosphates, and pyrethroids has been associated with impaired neurodevelopmental outcomes. Sex-specific differences following chronic insecticide exposure are rather common in vivo. Therefore, we assessed the chronic effects of in vitro exposure to different carbamates (carbaryl, methomyl and aldicarb), organophosphates [chlorpyrifos (CPF), chlorpyrifos-oxon (CPO), and 3,5,6,trichloropyridinol (TCP)], and pyrethroids [permethrin, alpha-cypermethrin and 3-phenoxy benzoic acid (3-PBA)] on neuronal network development in sex-separated rat primary cortical cultures using micro-electrode array (MEA) recordings. Our results indicate that exposure for 1 week to carbaryl inhibited neurodevelopment in male cultures, while a hyperexcitation was observed in female cultures. Methomyl and aldicarb evoked a hyperexcitation after 2 weeks of exposure, which was more pronounced in female cultures. In contrast to acute MEA results, exposure to ≥ 10 µM CPF caused hyperexcitation in both sexes after 10 days. Interestingly, exposure to 10 µM CPO induced a clear hyperexcitation after 10 days of exposure in male but not female cultures. Exposure to 100 µM CPO strongly inhibited neuronal development. Exposure to the type I pyrethroid permethrin resulted in a hyperexcitation at 10 µM and a decrease in neuronal development at 100 µM. In comparison, exposure to ≥ 10 µM of the type II pyrethroid alpha-cypermethrin decreased neuronal development. In female but not in male cultures, exposure to 1 and 10 µM permethrin changed (network) burst patterns, with female cultures having shorter (network) bursts with fewer spikes per (network) burst. Together, these results show that MEA recordings are suitable for measuring sex-specific developmental neurotoxicity in vitro. Additionally, pyrethroid exposure induced effects on neuronal network development at human-relevant concentrations. Finally, chronic exposure has different effects on neuronal functioning compared to acute exposure, highlighting the value of both exposure paradigms.
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Affiliation(s)
- Lennart V J van Melis
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - Anneloes M Peerdeman
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - Celia Arenas González
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - Regina G D M van Kleef
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - J Pepijn Wopken
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands
| | - Remco H S Westerink
- Neurotoxicology Research Group, Division of Toxicology, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD, Utrecht, The Netherlands.
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Sakaguchi K, Tawata S. Giftedness and atypical sexual differentiation: enhanced perceptual functioning through estrogen deficiency instead of androgen excess. Front Endocrinol (Lausanne) 2024; 15:1343759. [PMID: 38752176 PMCID: PMC11094242 DOI: 10.3389/fendo.2024.1343759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 04/15/2024] [Indexed: 05/18/2024] Open
Abstract
Syndromic autism spectrum conditions (ASC), such as Klinefelter syndrome, also manifest hypogonadism. Compared to the popular Extreme Male Brain theory, the Enhanced Perceptual Functioning model explains the connection between ASC, savant traits, and giftedness more seamlessly, and their co-emergence with atypical sexual differentiation. Overexcitability of primary sensory inputs generates a relative enhancement of local to global processing of stimuli, hindering the abstraction of communication signals, in contrast to the extraordinary local information processing skills in some individuals. Weaker inhibitory function through gamma-aminobutyric acid type A (GABAA) receptors and the atypicality of synapse formation lead to this difference, and the formation of unique neural circuits that process external information. Additionally, deficiency in monitoring inner sensory information leads to alexithymia (inability to distinguish one's own emotions), which can be caused by hypoactivity of estrogen and oxytocin in the interoceptive neural circuits, comprising the anterior insular and cingulate gyri. These areas are also part of the Salience Network, which switches between the Central Executive Network for external tasks and the Default Mode Network for self-referential mind wandering. Exploring the possibility that estrogen deficiency since early development interrupts GABA shift, causing sensory processing atypicality, it helps to evaluate the co-occurrence of ASC with attention deficit hyperactivity disorder, dyslexia, and schizophrenia based on phenotypic and physiological bases. It also provides clues for understanding the common underpinnings of these neurodevelopmental disorders and gifted populations.
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Affiliation(s)
- Kikue Sakaguchi
- Research Department, National Institution for Academic Degrees and Quality Enhancement of Higher Education (NIAD-QE), Kodaira-shi, Tokyo, Japan
| | - Shintaro Tawata
- Graduate School of Human Sciences, Sophia University, Chiyoda-ku, Tokyo, Japan
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Denney KA, Wu MV, Sun SED, Moon S, Tollkuhn J. Comparative analysis of gonadal hormone receptor expression in the postnatal house mouse, meadow vole, and prairie vole brain. Horm Behav 2024; 158:105463. [PMID: 37995608 PMCID: PMC11145901 DOI: 10.1016/j.yhbeh.2023.105463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 11/12/2023] [Accepted: 11/17/2023] [Indexed: 11/25/2023]
Abstract
The socially monogamous prairie vole (Microtus ochrogaster) and promiscuous meadow vole (Microtus pennsylvanicus) are closely related, but only prairie voles display long-lasting pair bonds, biparental care, and selective aggression towards unfamiliar individuals after pair bonding. These social behaviors in mammals are largely mediated by steroid hormone signaling in the social behavior network (SBN) of the brain. Hormone receptors are reproducible markers of sex differences that can provide more information than anatomy alone and can even be at odds with anatomical dimorphisms. We reasoned that behaviors associated with social monogamy in prairie voles may emerge in part from unique expression patterns of steroid hormone receptors in this species, and that these expression patterns would be more similar across males and females in prairie than in meadow voles or the laboratory mouse. To obtain insight into steroid hormone signaling in the developing prairie vole brain, we assessed expression of estrogen receptor alpha (Esr1), estrogen receptor beta (Esr2), and androgen receptor (Ar) within the SBN, using in situ hybridization at postnatal day 14 in mice, meadow, and prairie voles. We found species-specific patterns of hormone receptor expression in the hippocampus and ventromedial hypothalamus, as well as species differences in the sex bias of these markers in the principal nucleus of the bed nucleus of the stria terminalis. These findings suggest the observed differences in gonadal hormone receptor expression may underlie species differences in the display of social behaviors.
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Affiliation(s)
- Katherine A Denney
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA; Program in Neuroscience, Stony Brook University, Stony Brook, NY 11790, USA
| | - Melody V Wu
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Simón E D Sun
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Soyoun Moon
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Jessica Tollkuhn
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
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Phillips-Farfán BV, Quintanar BG, Reyes R, Fernández-Guasti A. Distribution of estrogen receptors alpha and beta in the brain of male rats with same-sex preference. Physiol Behav 2023; 268:114237. [PMID: 37192686 DOI: 10.1016/j.physbeh.2023.114237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/24/2023] [Accepted: 05/12/2023] [Indexed: 05/18/2023]
Abstract
Two distinct estrogen receptors (ERs) exist, ERα and ERβ. Both receptors participate in the sexual differentiation of the rat brain and likely participate in the regulation of adult sexual orientation (i.e. partner preference). This last idea was investigated herein by examining males treated with the aromatase inhibitor, letrozole, administered prenatally (0.56 μg/kg G10-22). This treatment usually provokes same-sex preference in 1-2 males per litter. Vehicle-treated males (with female preference) and females in spontaneous proestrus (with male preference) were included as controls. ERα and ERβ expression was analyzed by immunohistochemistry in brain areas known to control masculine sexual behavior and partner preference, like the medial preoptic area (MPOA), bed nucleus of the stria terminalis (BNST), medial amygdala (MeA) and ventromedial hypothalamic nucleus (VMH), as well as other brain regions suspected to participate in these processes. In addition, serum levels of estradiol were determined in all male groups. Letrozole-treated male rats that preferred sexually experienced males (LPM) showed over-expressed ERα in the hippocampal cornu Ammonis (CA 1, 3, 4) and dentate gyrus. The LPM group showed up-regulated ERβ expression in the CA2 and reticular thalamic nucleus. The levels of estradiol did not differ between the groups. The higher expression of ERs in these males was different than their expression in females, with male sex-preference. This suggests that males with same-sex preference showed a unique brain, this sui generis steroid receptor expression probably participates in the biological underpinnings of sexual preference.
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Affiliation(s)
| | | | - Rebeca Reyes
- Departament of Pharmacobiology, Cinvestav, Unidad Coapa
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Cisneros-Larios B, Elias CF. Sex differences in the coexpression of prokineticin receptor 2 and gonadal steroids receptors in mice. Front Neuroanat 2023; 16:1057727. [PMID: 36686573 PMCID: PMC9853983 DOI: 10.3389/fnana.2022.1057727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/20/2022] [Indexed: 01/07/2023] Open
Abstract
Loss-of-function mutations in prokineticin 2 (PROK2) and the cognate receptor prokineticin receptor 2 (PROKR2) genes have been implicated in reproductive deficits characteristic of Kallmann Syndrome (KS). Knock out of Prokr2 gene produces the KS-like phenotype in mice resulting in impaired migration of gonadotropin releasing hormone (GnRH) neurons, olfactory bulb dysgenesis, and infertility. Beyond a developmental role, pharmacological and genetic studies have implicated PROKR2 in the control of the estrous cycle in mice. However, PROKR2 is expressed in several reproductive control sites but the brain nuclei associated with reproductive control in adult mice have not been defined. We set out to determine if ProkR2 neurons in both male and female mouse brains directly sense changes in the gonadal steroids milieu. We focused on estrogen receptor α (ERα) and androgen receptor (AR) due to their well-described function in reproductive control via actions in the brain. We found that the ProkR2-Cre neurons in the posterior nucleus of the amygdala have the highest colocalization with ERα and AR in a sex-specific manner. Few colocalization was found in the lateral septum and in the bed nucleus of the stria terminalis, and virtually no colocalization was observed in the medial amygdala. Our findings indicate that the posterior nucleus of the amygdala is the main site where PROKR2 neurons may regulate aspects of the reproductive function and social behavior in adult mice.
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Affiliation(s)
- Brenda Cisneros-Larios
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
- Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States
| | - Carol Fuzeti Elias
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
- Elizabeth W. Caswell Diabetes Institute, University of Michigan, Ann Arbor, MI, United States
- Department of Gynecology and Obstetrics, University of Michigan, Ann Arbor, MI, United States
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States
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Sedwick VM, Autry AE. Anatomical and molecular features of the amygdalohippocampal transition area and its role in social and emotional behavior processes. Neurosci Biobehav Rev 2022; 142:104893. [PMID: 36179917 PMCID: PMC11106034 DOI: 10.1016/j.neubiorev.2022.104893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 09/21/2022] [Accepted: 09/24/2022] [Indexed: 02/04/2023]
Abstract
The amygdalohippocampal transition area (AHi) has emerged as a critical nucleus of sociosexual behaviors such as mating, parenting, and aggression. The AHi has been overlooked in rodent and human amygdala studies until recently. The AHi is hypothesized to play a role in metabolic and cognitive functions as well as social behaviors based on its connectivity and molecular composition. The AHi is small nucleus rich in neuropeptide and hormone receptors and is contiguous with the ventral subiculum of the hippocampus-hence its designation as a "transition area". Literature focused on the AHi can be difficult to interpret because of changing nomenclature and conflation with neighboring nuclei. Here we summarize what is currently known about AHi structure and development, connections throughout the brain, molecular composition, and functional significance. We aim to delineate current knowledge regarding the AHi, identify potential functions with supporting evidence, and ultimately make clear the importance of the AHi in sociosexual function.
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Affiliation(s)
- Victoria M Sedwick
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Anita E Autry
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, NY, USA.
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Witchey SK, Doyle MG, Fredenburg JD, St Armour G, Horman B, Odenkirk MT, Aylor DL, Baker ES, Patisaul HB. Impacts of Gestational FireMaster 550 Exposure on the Neonatal Cortex Are Sex Specific and Largely Attributable to the Organophosphate Esters. Neuroendocrinology 2022; 113:1262-1282. [PMID: 36075192 PMCID: PMC9992460 DOI: 10.1159/000526959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 08/24/2022] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Flame retardants (FRs) are common bodily and environmental pollutants, creating concern about their potential toxicity. We and others have found that the commercial mixture FireMaster® 550 (FM 550) or its individual brominated (BFR) and organophosphate ester (OPFR) components are potential developmental neurotoxicants. Using Wistar rats, we previously reported that developmental exposure to FM 550 or its component classes produced sex- and compound-specific effects on adult socioemotional behaviors. The underlying mechanisms driving the behavioral phenotypes are unknown. METHODS To further mechanistic understanding, here we conducted transcriptomics in parallel with a novel lipidomics approach using cortical tissues from newborn siblings of the rats in the published behavioral study. Inclusion of lipid composition is significant because it is rarely examined in developmental neurotoxicity studies. Pups were gestationally exposed via oral dosing to the dam to FM 550 or the BFR or OPFR components at environmentally relevant doses. RESULTS The neonatal cortex was highly sexually dimorphic in lipid and transcriptome composition, and males were more significantly impacted by FR exposure. Multiple adverse modes of action for the BFRs and OPFRs on neurodevelopment were identified, with the OPFRs being more disruptive than the BFRs via multiple mechanisms including dysregulation of mitochondrial function and disruption of cholinergic and glutamatergic systems. Disrupted mitochondrial function by environmental factors has been linked to a higher risk of autism spectrum disorders and neurodegenerative disorders. Impacted lipid classes included ceramides, sphingomyelins, and triacylglycerides. Robust ceramide upregulation in the OPFR females could suggest a heightened risk of brain metabolic disease. CONCLUSIONS This study reveals multiple mechanisms by which the components of a common FR mixture are developmentally neurotoxic and that the OPFRs may be the compounds of greatest concern.
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Affiliation(s)
- Shannah K Witchey
- Department of Biological Sciences, NC State University, Raleigh, North Carolina, USA
| | - Michael G Doyle
- Department of Chemistry, NC State University, Raleigh, North Carolina, USA
| | - Jacob D Fredenburg
- Department of Biological Sciences, NC State University, Raleigh, North Carolina, USA
| | - Genevieve St Armour
- Department of Biological Sciences, NC State University, Raleigh, North Carolina, USA
| | - Brian Horman
- Department of Biological Sciences, NC State University, Raleigh, North Carolina, USA
| | - Melanie T Odenkirk
- Department of Chemistry, NC State University, Raleigh, North Carolina, USA
| | - David L Aylor
- Department of Biological Sciences, NC State University, Raleigh, North Carolina, USA
- Center for Human Health and the Environment, NC State University, Raleigh, North Carolina, USA
| | - Erin S Baker
- Department of Chemistry, NC State University, Raleigh, North Carolina, USA
| | - Heather B Patisaul
- Center for Human Health and the Environment, NC State University, Raleigh, North Carolina, USA
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Extrahypothalamic Control of Energy Balance and Its Connection with Reproduction: Roles of the Amygdala. Metabolites 2021; 11:metabo11120837. [PMID: 34940594 PMCID: PMC8708157 DOI: 10.3390/metabo11120837] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/02/2021] [Accepted: 12/02/2021] [Indexed: 11/24/2022] Open
Abstract
Body energy and metabolic homeostasis are exquisitely controlled by multiple, often overlapping regulatory mechanisms, which permit the tight adjustment between fuel reserves, internal needs, and environmental (e.g., nutritional) conditions. As such, this function is sensitive to and closely connected with other relevant bodily systems, including reproduction and gonadal function. The aim of this mini-review article is to summarize the most salient experimental data supporting a role of the amygdala as a key brain region for emotional learning and behavior, including reward processing, in the physiological control of feeding and energy balance. In particular, a major focus will be placed on the putative interplay between reproductive signals and amygdala pathways, as it pertains to the control of metabolism, as complementary, extrahypothalamic circuit for the integral control of energy balance and gonadal function.
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Patisaul HB. REPRODUCTIVE TOXICOLOGY: Endocrine disruption and reproductive disorders: impacts on sexually dimorphic neuroendocrine pathways. Reproduction 2021; 162:F111-F130. [PMID: 33929341 PMCID: PMC8484365 DOI: 10.1530/rep-20-0596] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 04/30/2021] [Indexed: 11/08/2022]
Abstract
We are all living with hundreds of anthropogenic chemicals in our bodies every day, a situation that threatens the reproductive health of present and future generations. This review focuses on endocrine-disrupting compounds (EDCs), both naturally occurring and man-made, and summarizes how they interfere with the neuroendocrine system to adversely impact pregnancy outcomes, semen quality, age at puberty, and other aspects of human reproductive health. While obvious malformations of the genitals and other reproductive organs are a clear sign of adverse reproductive health outcomes and injury to brain sexual differentiation, the hypothalamic-pituitary-gonadal (HPG) axis can be much more difficult to discern, particularly in humans. It is well-established that, over the course of development, gonadal hormones shape the vertebrate brain such that sex-specific reproductive physiology and behaviors emerge. Decades of work in neuroendocrinology have elucidated many of the discrete and often very short developmental windows across pre- and postnatal development in which this occurs. This has allowed toxicologists to probe how EDC exposures in these critical windows can permanently alter the structure and function of the HPG axis. This review includes a discussion of key EDC principles including how latency between exposure and the emergence of consequential health effects can be long, along with a summary of the most common and less well-understood EDC modes of action. Extensive examples of how EDCs are impacting human reproductive health, and evidence that they have the potential for multi-generational physiological and behavioral effects are also provided.
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Affiliation(s)
- Heather B Patisaul
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina, USA
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Patisaul HB. Endocrine disrupting chemicals (EDCs) and the neuroendocrine system: Beyond estrogen, androgen, and thyroid. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2021; 92:101-150. [PMID: 34452685 DOI: 10.1016/bs.apha.2021.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Hundreds of anthropogenic chemicals occupy our bodies, a situation that threatens the health of present and future generations. This chapter focuses on endocrine disrupting compounds (EDCs), both naturally occurring and man-made, that affect the neuroendocrine system to adversely impact health, with an emphasis on reproductive and metabolic pathways. The neuroendocrine system is highly sexually dimorphic and essential for maintaining homeostasis and appropriately responding to the environment. Comprising both neural and endocrine components, the neuroendocrine system is hormone sensitive throughout life and touches every organ system in the body. The integrative nature of the neuroendocrine system means that EDCs can have multi-system effects. Additionally, because gonadal hormones are essential for the sex-specific organization of numerous neuroendocrine pathways, endocrine disruption of this programming can lead to permanent deficits. Included in this review is a brief history of the neuroendocrine disruption field and a thorough discussion of the most common and less well understood neuroendocrine disruption modes of action. Also provided are extensive examples of how EDCs are likely contributing to neuroendocrine disorders such as obesity, and evidence that they have the potential for multi-generational effects.
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Affiliation(s)
- Heather B Patisaul
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, NC, United States.
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Heindel JJ, Belcher S, Flaws JA, Prins GS, Ho SM, Mao J, Patisaul HB, Ricke W, Rosenfeld CS, Soto AM, Vom Saal FS, Zoeller RT. Data integration, analysis, and interpretation of eight academic CLARITY-BPA studies. Reprod Toxicol 2020; 98:29-60. [PMID: 32682780 PMCID: PMC7365109 DOI: 10.1016/j.reprotox.2020.05.014] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 05/03/2020] [Accepted: 05/25/2020] [Indexed: 12/12/2022]
Abstract
"Consortium Linking Academic and Regulatory Insights on BPA Toxicity" (CLARITY-BPA) was a comprehensive "industry-standard" Good Laboratory Practice (GLP)-compliant 2-year chronic exposure study of bisphenol A (BPA) toxicity that was supplemented by hypothesis-driven independent investigator-initiated studies. The investigator-initiated studies were focused on integrating disease-associated, molecular, and physiological endpoints previously found by academic scientists into an industry standard guideline-compliant toxicity study. Thus, the goal of this collaboration was to provide a more comprehensive dataset upon which to base safety standards and to determine whether industry-standard tests are as sensitive and predictive as molecular and disease-associated endpoints. The goal of this report is to integrate the findings from the investigator-initiated studies into a comprehensive overview of the observed impacts of BPA across the multiple organs and systems analyzed. For each organ system, we provide the rationale for the study, an overview of methodology, and summarize major findings. We then compare the results of the CLARITY-BPA studies across organ systems with the results of previous peer-reviewed studies from independent labs. Finally, we discuss potential influences that contributed to differences between studies. Developmental exposure to BPA can lead to adverse effects in multiple organs systems, including the brain, prostate gland, urinary tract, ovary, mammary gland, and heart. As published previously, many effects were at the lowest dose tested, 2.5μg/kg /day, and many of the responses were non-monotonic. Because the low dose of BPA affected endpoints in the same animals across organs evaluated in different labs, we conclude that these are biologically - and toxicologically - relevant.
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Affiliation(s)
- Jerrold J Heindel
- Healthy Environment and Endocrine Disruptor Strategies Commonweal, Bolinas, CA 94924, United States.
| | - Scott Belcher
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, United States
| | - Jodi A Flaws
- Department of Comparative Biosciences, University of Illinois at Urbana-Champaign, Urbana, IL 61802, United States
| | - Gail S Prins
- Department of Urology, College of Medicine, University of Illinois at Chicago, Chicago IL 60612, United States
| | - Shuk-Mei Ho
- Department of Environmental Health, University of Cincinnati, Cincinnati OH 45267, United States; Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, United States
| | - Jiude Mao
- Biomedical Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, United States
| | - Heather B Patisaul
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, United States
| | - William Ricke
- Department of Urology, University of Wisconsin, Madison WI 53705, United States
| | - Cheryl S Rosenfeld
- Biomedical Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, United States
| | - Ana M Soto
- Tufts University, Boston, MA 02111, United States
| | - Frederick S Vom Saal
- Department of Biology, University of Missouri, Columbia, MO 65211, United States
| | - R Thomas Zoeller
- Department of Biology, University of Massachusetts, Amherst, MA 01003, United States
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Le Moëne O, Ramírez-Rentería ML, Ågmo A. Male and female immediate fear reaction to white noise in a semi-natural environment: A detailed behavioural analysis of the role of sex and oestrogen receptors. J Neuroendocrinol 2020; 32:e12902. [PMID: 32985022 DOI: 10.1111/jne.12902] [Citation(s) in RCA: 2] [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: 03/11/2020] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 01/18/2023]
Abstract
In classical rodent anxiety models, females usually display lower anxiety than males, whereas anxiety disorders are more prevalent in women. Perhaps this contradiction is caused by the use of behavioural models with low external validity. Therefore, we analysed immediate reactions to a sudden 90-dB white noise in a semi-natural environment. We observed mixed-sex groups of rats for the 60 seconds preceding noise onset and the first 60 seconds of exposure. White noise elicited fear-specific behaviours hiding alone and huddling. It also increased exploratory and ambulatory behaviours, although only in the burrow zone farthest from the open area. Thus, in a semi-natural environment, white noise enhanced motor activity as a product of fear-induced general arousal. Then, we compared male and female sexual, social, exploratory and anxiety-related behaviour, and found little sex difference. This absence of behavioural effect, also observed in other studies, might be a result of our study design, a familiar environment with an ecologically relevant social context. Fear and anxiety responses are modulated by oestrogens through the activation of oestrogen receptors α and β. Thus, in a third part of out study, we analysed how treatment with either oil, oestradiol benzoate (EB), an agonist to the oestrogen receptor α (propylpyrazoletriol [PPT]) or β (diarylpropionitrile [DPN]) influenced female behaviour. The effect of treatment was limited, both EB and PPT stimulated motor activity in the open area before white noise, probably because of sexual activity. PPT increased the probability of fleeing from the noise, and decreased the latency to do so, which is consistent with a pattern of anxiogenic properties found in previous studies. Contrary to reports in classical procedures, we failed to detect any effect of DPN on immediate fear reactions in a semi-natural environment.
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Affiliation(s)
- Olivia Le Moëne
- Department of Psychology, University of Tromsø, Tromsø, Norway
| | | | - Anders Ågmo
- Department of Psychology, University of Tromsø, Tromsø, Norway
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Gradual wiring of olfactory input to amygdala feedback circuits. Sci Rep 2020; 10:5871. [PMID: 32245993 PMCID: PMC7125095 DOI: 10.1038/s41598-020-62457-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 03/11/2020] [Indexed: 11/08/2022] Open
Abstract
The amygdala facilitates odor driven behavioral responses by enhancing the saliency of olfactory signals. Before this processing, olfactory input is refined through the feedback provided by amygdala corticofugal projection (ACPs). Although the saliency of odor signals is subject to developmental changes, the stage at which this cortical feedback first occurs is not known. Using optogenetically-assisted intracellular recordings of the mouse cortical amygdala, we identified changes in the electrophysiological properties of ACPs at different developmental stages. These were consistent with a decrease in neuronal excitability and an increase in the amount of incoming accessory olfactory bulb (AOB) inputs, as confirmed by estimates of release probability, quantal size and contact number at the AOB-to-ACP synapse. Moreover, the proportion of ACPs activated in response to odors was dependent on the stage of development as revealed by c-Fos expression analysis. These results update standard accounts of how the amygdala processes social signals by emphasizing the occurrence of critical periods in the development of its sensory gating functions.
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14
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Patisaul HB. Achieving CLARITY on bisphenol A, brain and behaviour. J Neuroendocrinol 2020; 32:e12730. [PMID: 31063678 PMCID: PMC10947534 DOI: 10.1111/jne.12730] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 04/28/2019] [Accepted: 05/02/2019] [Indexed: 12/18/2022]
Abstract
There is perhaps no endocrine disrupting chemical more controversial than bisphenol A (BPA). Comprising a high-volume production chemical used in a variety of applications, BPA has been linked to a litany of adverse health-related outcomes, including effects on brain sexual differentiation and behaviour. Risk assessors preferentially rely on classical guideline-compliant toxicity studies over studies published by academic scientists, and have generally downplayed concerns about the potential risks that BPA poses to human health. It has been argued, however, that, because traditional toxicity studies rarely contain neural endpoints, and only a paucity of endocrine-sensitive endpoints, they are incapable of fully evaluating harm. To address current controversies on the safety of BPA, the United States National Institute of Environmental Health Sciences, the National Toxicology Program (NTP), and the US Food and Drug Administration established the Consortium Linking Academic and Regulatory Insights on BPA Toxicity (CLARITY-BPA). CLARITY-BPA performed a classical regulatory-style toxicology study (Core study) in conjunction with multiple behavioural, molecular and cellular studies conducted by academic laboratories (grantee studies) using a collaboratively devised experimental framework and the same animals and tissues. This review summarises the results from the grantee studies that focused on brain and behaviour. Evidence of altered neuroendocrine development, including age- and sex-specific expression of oestrogen receptor (ER)α and ERβ, and the abrogation of brain and behavioural sexual dimorphisms, supports the conclusion that developmental BPA exposure, even at doses below what regulatory agencies regard as "safe" for humans, contribute to brain and behavioural change. The consistency and the reproducibility of the effects across CLARITY-BPA and prior studies using the same animal strain and almost identical experimental conditions are compelling. Combined analysis of all of the data from the CLARITY-BPA project is underway at the NTP and a final report expected in late 2019.
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Affiliation(s)
- Heather B Patisaul
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina
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15
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Witchey SK, Fuchs J, Patisaul HB. Perinatal bisphenol A (BPA) exposure alters brain oxytocin receptor (OTR) expression in a sex- and region- specific manner: A CLARITY-BPA consortium follow-up study. Neurotoxicology 2019; 74:139-148. [PMID: 31251963 PMCID: PMC6750986 DOI: 10.1016/j.neuro.2019.06.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 06/17/2019] [Accepted: 06/24/2019] [Indexed: 12/15/2022]
Abstract
Bisphenol A (BPA) is a well-characterized endocrine disrupting chemical (EDC) used in plastics, epoxy resins and other products. Neurodevelopmental effects of BPA exposure are a major concern with multiple rodent and human studies showing that early life BPA exposure may impact the developing brain and sexually dimorphic behaviors. The CLARITY-BPA (Consortium Linking Academic and Regulatory Insights on BPA Toxicity) program was established to assess multiple endpoints, including neural, across a wide dose range. Studies from our lab as part of (and prior to) CLARITY-BPA have shown that BPA disrupts estrogen receptor expression in the developing brain, and some evidence of oxytocin (OT) and oxytocin receptor (OTR) disruption in the hypothalamus and amygdala. While BPA disruption of steroid hormone function is well documented, less is known about its capacity to alter nonapeptide signals. In this CLARITY-BPA follow up study, we used remaining juvenile rat tissues to test the hypothesis that developmental BPA exposure affects OTR expression across the brain. Perinatal BPA exposure (2.5, 25, or 2500 μg/kg body weight (bw)/day) spanned gestation and lactation with dams gavaged from gestational day 6 until birth and then the offspring gavaged directly through weaning. Ethinyl estradiol (0.5 μg/kg bw/day) was used as a reference estrogen. Animals of both sexes were sacrificed as juveniles and OTR expression assessed by receptor binding. Our results demonstrate prenatal exposure to BPA can eliminate sex differences in OTR expression in three hypothalamic regions, and that male OTR expression may be more susceptible. Our data also identify a sub-region of the BNST with sexually dimorphic OTR expression not previously reported in juvenile rats that is also susceptible to BPA.
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Affiliation(s)
- Shannah K Witchey
- Department of Biological Sciences, NC State University, Raleigh, NC, 27695, United States
| | - Joelle Fuchs
- Department of Biological Sciences, NC State University, Raleigh, NC, 27695, United States
| | - Heather B Patisaul
- Department of Biological Sciences, NC State University, Raleigh, NC, 27695, United States; Center for Human Health and the Environment, NC State University, Raleigh, NC, 27695, United States.
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16
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Prins GS, Patisaul HB, Belcher SM, Vandenberg LN. CLARITY-BPA academic laboratory studies identify consistent low-dose Bisphenol A effects on multiple organ systems. Basic Clin Pharmacol Toxicol 2018; 125 Suppl 3:14-31. [PMID: 30207065 DOI: 10.1111/bcpt.13125] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 08/31/2018] [Indexed: 12/13/2022]
Abstract
Bisphenol A (BPA) is a high-production chemical used in a variety of applications worldwide. While BPA has been documented as an endocrine-disrupting chemical (EDC) having adverse health-related outcomes in multiple studies, risk assessment for BPA has lagged due to reliance on guideline toxicology studies over academic ones with end-points considered more sensitive and appropriate. To address current controversies on BPA safety, the United States National Institute of Environmental Health Sciences (NIEHS), the National Toxicology Program (NTP) and the Food and Drug Administration (FDA) established the Consortium Linking Academic and Regulatory Insights on BPA Toxicity (CLARITY-BPA) using the NCTR Sprague-Dawley rats. The goal of CLARITY-BPA is to perform a traditional regulatory toxicology study (Core study) in conjunction with multiple behavioural, molecular and cellular studies by academic laboratories focused on previously identified BPA-sensitive organ systems (Academic studies). Combined analysis of the data from both study types will be undertaken by the NTP with the aim of resolving uncertainties on BPA toxicity. To date, the Core study has been completed and a draft report released. Most of the academic studies have also been finalized and published in peer-reviewed journals. In light of this important milestone, the PPTOX-VI meeting held in the Faroe Islands, 27-30 May 2018 devoted a plenary session to CLARITY-BPA with presentations by multiple investigators with the purpose of highlighting key outcome. This MiniReview synthesizes the results of three academic studies presented at this plenary session, evaluates recently published findings by other CLARITY-BPA academic studies to provide an early combined overview of this emerging data and places this in the context of the Core study findings. This co-ordinated effort revealed a plethora of significant BPA effects across multiple organ systems and BPA doses with non-monotonic responses across the dose range utilized. Remarkably consistent across most studies, including the Core study, are low-dose effects (2.5, 25 and 250 μg BPA/kg body-weight). Collectively, the findings highlighted herein corroborate a significant body of evidence that documents adverse effects of BPA at doses relevant to human exposures and emphasizes the need for updated risk assessment analysis.
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Affiliation(s)
- Gail S Prins
- Departments of Urology, Pathology, and Physiology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois.,Division of Epidemiology & Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, Illinois.,Chicago Center for Health and Environment (CACHET), University of Illinois at Chicago, Chicago, Illinois
| | - Heather B Patisaul
- Department of Biological Sciences and the Center for Human Health and the Environment (CHHE), North Carolina State University, Raleigh, North Carolina
| | - Scott M Belcher
- Department of Biological Sciences and the Center for Human Health and the Environment (CHHE), North Carolina State University, Raleigh, North Carolina
| | - Laura N Vandenberg
- Department of Environmental Health Sciences, University of Massachusetts-Amherst, School of Public Health & Health Sciences, Amherst, Massachusetts
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17
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Stephens SBZ, Di Giorgio NP, Liaw RB, Parra RA, Yang JA, Chahal N, Lux-Lantos VA, Kauffman AS. Estradiol-Dependent and -Independent Stimulation of Kiss1 Expression in the Amygdala, BNST, and Lateral Septum of Mice. Endocrinology 2018; 159:3389-3402. [PMID: 30107405 PMCID: PMC6112601 DOI: 10.1210/en.2018-00583] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 08/06/2018] [Indexed: 12/27/2022]
Abstract
Kisspeptin, encoded by Kiss1, activates reproduction by stimulating GnRH neurons. Although most Kiss1 neurons are located in the hypothalamus, smaller Kiss1 populations also reside in the medial amygdala (MeA), bed nucleus of the stria terminalis (BnST), and lateral septum (LS). However, very little is known about the regulation and function of these extra-hypothalamic Kiss1 neurons. This study focused on the roles and interactions of two signaling factors, estradiol (E2) and GABA, known to stimulate and inhibit, respectively, extra-hypothalamic Kiss1 expression. First, using estrogen receptor (ER)α knockout (KO) and βERKO mice, we demonstrated that Kiss1 in both the BnST and LS is stimulated by E2, as occurs in the MeA, and that this E2 upregulation occurs via ERα, but not ERβ. Second, using GABABR KO and wild-type mice, we determined that whereas E2 normally increases extra-hypothalamic Kiss1 levels, such upregulation by E2 is further enhanced by the concurrent absence of GABABR signaling in the MeA and LS, but not the BnST. Third, we demonstrated that when GABABR signaling is absent, the additional removal of gonadal sex steroids does not abolish Kiss1 expression in the MeA and BnST, and in some cases the LS. Thus, Kiss1 expression in these extra-hypothalamic regions is not solely dependent on E2 stimulation. Finally, we demonstrated a significant positive correlation between Kiss1 levels in the MeA, BnST, and LS, but not between these regions and the hypothalamus (anteroventral periventricular nucleus/periventricular nucleus). Collectively, our findings indicate that both E2 and GABA independently regulate all three extra-hypothalamic Kiss1 populations, but their regulatory interactions may vary by brain region and additional yet-to-be-identified factors are likely involved.
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Affiliation(s)
- Shannon B Z Stephens
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
| | - Noelia P Di Giorgio
- Institute of Biology and Experimental Medicine, National Scientific and Technical Research Council, Buenos Aires, Argentina
| | - Reanna B Liaw
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
| | - Ruby A Parra
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
| | - Jennifer A Yang
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
| | - Navdeep Chahal
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
| | - Victoria A Lux-Lantos
- Institute of Biology and Experimental Medicine, National Scientific and Technical Research Council, Buenos Aires, Argentina
| | - Alexander S Kauffman
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, La Jolla, California
- Correspondence: Alexander S. Kauffman, PhD, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California, San Diego, Leichtag Building, Room 3A-15, 9500 Gilman Drive, No. 0674, La Jolla, California 92093. E-mail:
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18
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Pałasz A, Pałka M, Filipczyk Ł, Menezes IC, Rojczyk E, Worthington JJ, Piwowarczyk-Nowak A, Krzystanek M, Wiaderkiewicz R. Effect of long-term treatment with classical neuroleptics on NPQ/spexin, kisspeptin and POMC mRNA expression in the male rat amygdala. J Neural Transm (Vienna) 2018; 125:1099-1105. [PMID: 29488100 PMCID: PMC5999179 DOI: 10.1007/s00702-018-1868-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 02/22/2018] [Indexed: 12/16/2022]
Abstract
Neuroleptics modulate the expression level of some regulatory neuropeptides in the brain. However, if these therapeutics influence the peptidergic circuits in the amygdala remains unclear. This study specifies the impact profile of the classical antipsychotic drugs on mRNA expression of the spexin/NPQ, kisspeptin-1 and POMC in the rat amygdala. Animals were treated with haloperidol and chlorpromazine for 28 days prior to transcript quantification via qPCR. Haloperidol and chlorpromazine induced a change in the expression of all neuropeptides analyzed. Both drugs led to the decrease of Kiss-1 expression, whereas in POMC and spexin/NPQ their up-regulation in the amygdala was detected. These modulating effects on may represent alternative, so far unknown mechanisms, of classical antipsychotic drugs triggering pharmacological responses.
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Affiliation(s)
- Artur Pałasz
- Department of Histology, School of Medicine in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland.
| | - Marcelina Pałka
- Department of Histology, School of Medicine in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland
| | - Łukasz Filipczyk
- Department of Histology, School of Medicine in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland
| | - Itiana Castro Menezes
- Department of Neurosciences and Behaviour, Faculty of Medicine, University of São Paulo, Av. Bandeirantes 3900, Ribeirão Preto, São Paulo, 14049-900, Brazil
| | - Ewa Rojczyk
- Department of Descriptive and Topographic Anatomy, School of Medicine with Division of Dentistry in Zabrze, Medical University of Silesia, ul. Jordana 19, 41-808, Zabrze, Poland
| | - John J Worthington
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YQ, UK
| | - Aneta Piwowarczyk-Nowak
- Department of Anatomy, School of Medicine in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland
| | - Marek Krzystanek
- Department and Clinic of Psychiatric Rehabilitation, School of Medicine in Katowice, Medical University of Silesia, ul. Ziolowa 45/47, 40-635, Katowice, Poland
| | - Ryszard Wiaderkiewicz
- Department of Histology, School of Medicine in Katowice, Medical University of Silesia, ul. Medyków 18, 40-752, Katowice, Poland
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19
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Pałasz A, Janas-Kozik M, Borrow A, Arias-Carrión O, Worthington JJ. The potential role of the novel hypothalamic neuropeptides nesfatin-1, phoenixin, spexin and kisspeptin in the pathogenesis of anxiety and anorexia nervosa. Neurochem Int 2018; 113:120-136. [DOI: 10.1016/j.neuint.2017.12.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/13/2017] [Accepted: 12/14/2017] [Indexed: 02/07/2023]
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20
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Rosinger ZJ, Jacobskind JS, Park SG, Justice NJ, Zuloaga DG. Distribution of corticotropin-releasing factor receptor 1 in the developing mouse forebrain: A novel sex difference revealed in the rostral periventricular hypothalamus. Neuroscience 2017; 361:167-178. [PMID: 28823817 DOI: 10.1016/j.neuroscience.2017.08.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 07/19/2017] [Accepted: 08/09/2017] [Indexed: 12/16/2022]
Abstract
Corticotropin-releasing factor (CRF) signaling through CRF receptor 1 (CRFR1) regulates autonomic, endocrine and behavioral responses to stress and has been implicated in the pathophysiology of several disorders including anxiety, depression, and addiction. Using a validated CRFR1 reporter mouse line (bacterial artificial chromosome identified by green fluorescence protein (BAC GFP-CRFR1)), we investigated the distribution of CRFR1 in the developing mouse forebrain. Distribution of CRFR1 was investigated at postnatal days (P) 0, 4, and 21 in male and female mice. CRFR1 increased with age in several regions including the medial amygdala, arcuate nucleus, paraventricular hypothalamus, medial septum, CA1 hippocampal area, and the lateral habenula. Regions showing decreased CRFR1 expression with increased age include the intermediate portion of the periventricular hypothalamic nucleus, and CA3 hippocampal area. We report a sexually dimorphic expression of CRFR1 within the rostral portion of the anteroventral periventricular nucleus of the hypothalamus (AVPV/PeN), a region known to regulate ovulation, reproductive and maternal behaviors. Females had a greater number of CRFR1-GFP-ir cells at all time points in the AVPV/PeN and CRFR1-GFP-ir was nearly absent in males by P21. Overall, alterations in CRFR1-GFP-ir distribution based on age and sex may contribute to observed age- and sex-dependent differences in stress regulation.
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Affiliation(s)
| | | | - Shannon G Park
- University at Albany, Department of Psychology, Albany, NY 12222, USA
| | - Nicholas J Justice
- Center for Metabolic and Degenerative Diseases, Institute of Molecular Medicine, University of Texas Health Sciences Center, Houston, TX, USA
| | - Damian G Zuloaga
- University at Albany, Department of Psychology, Albany, NY 12222, USA.
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21
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Molecular cloning of ESR2 and gene expression analysis of ESR1 and ESR2 in the pituitary gland of the Chinese alligator ( Alligator sinensis ) during female reproductive cycle. Gene 2017; 623:15-23. [DOI: 10.1016/j.gene.2017.04.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 01/04/2017] [Accepted: 04/12/2017] [Indexed: 02/02/2023]
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22
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Cisternas CD, Cabrera Zapata LE, Arevalo MA, Garcia-Segura LM, Cambiasso MJ. Regulation of aromatase expression in the anterior amygdala of the developing mouse brain depends on ERβ and sex chromosome complement. Sci Rep 2017; 7:5320. [PMID: 28706210 PMCID: PMC5509695 DOI: 10.1038/s41598-017-05658-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/01/2017] [Indexed: 12/11/2022] Open
Abstract
During development sex differences in aromatase expression in limbic regions of mouse brain depend on sex chromosome factors. Genes on the sex chromosomes may affect the hormonal regulation of aromatase expression and this study was undertaken to explore that possibility. Male E15 anterior amygdala neuronal cultures expressed higher levels of aromatase (mRNA and protein) than female cultures. Furthermore, treatment with oestradiol (E2) or dihydrotestosterone (DHT) increased Cyp19a1 expression and aromatase protein levels only in female neuronal cultures. The effect of E2 on aromatase expression was not imitated by oestrogen receptor (ER) α agonist PPT or the GPER agonist G1, but it was fully reproduced by DPN, a specific ligand of ERβ. By contrast, the effect of DHT on aromatase expression was not blocked by the anti-androgen flutamide, but completely abrogated by the ERβ antagonist PHTPP. Experiments using the four core genotype model showed a sex chromosome effect in ERβ expression (XY > XX) and regulation by E2 or DHT (only XX respond) in amygdala neurons. In conclusion, sex chromosome complement governs the hormonal regulation of aromatase expression through activation of ERβ in developing mouse brain.
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Affiliation(s)
- Carla Daniela Cisternas
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina.,Departamento de Biología Bucal, Facultad de Odontología -Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Lucas Ezequiel Cabrera Zapata
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - María Angeles Arevalo
- Instituto Cajal, CSIC, Madrid, Spain.,Ciber de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - Luis Miguel Garcia-Segura
- Instituto Cajal, CSIC, Madrid, Spain.,Ciber de Investigación Biomédica en Red de Fragilidad y Envejecimiento Saludable (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
| | - María Julia Cambiasso
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina. .,Departamento de Biología Bucal, Facultad de Odontología -Universidad Nacional de Córdoba, Córdoba, Argentina.
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23
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Wright EC, Johnson SA, Hao R, Kowalczyk AS, Greenberg GD, Sanchez EO, Laman-Maharg A, Trainor BC, Rosenfeld CS. Exposure to extrinsic stressors, social defeat or bisphenol A, eliminates sex differences in DNA methyltransferase expression in the amygdala. J Neuroendocrinol 2017; 29:10.1111/jne.12475. [PMID: 28406523 PMCID: PMC5501704 DOI: 10.1111/jne.12475] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 03/22/2017] [Accepted: 03/30/2017] [Indexed: 12/24/2022]
Abstract
Chemical and psychological stressors can exert long lasting changes in brain function and behaviour. Changes in DNA methylation have been shown to be an important mechanism mediating long lasting changes in neural function and behaviour, especially for anxiety-like or stress responses. In the present study, we examined the effects of either a social or chemical stressor on DNA methyltransferase (DNMT) gene expression in the amygdala, an important brain region modulating stress responses and anxiety. In adult California mice (Peromyscus californicus) that were naïve to social defeat, females had higher levels of Dnmt1 expression in punch samples of the central amygdala (CeA) than males. In addition, mice that underwent social defeat stress showed reduced Dnmt1 and Dnmt3a expression in the CeA of females but not males. A second study using more anatomically specific punch samples replicated these effects for Dnmt1. Perinatal exposure (spanning from periconception through lactation) to bisphenol A or ethinyl oestradiol (oestrogens in birth control pills) also abolished sex differences in Dnmt1 expression in the CeA but not the basolateral amygdala. These findings identify a robust sex difference in Dnmt1 expression in the CeA that is sensitive to both psychological and chemical stressors. Future studies should aim to examine the impact of psychological and chemical stressors on DNA methylation in the CeA and also investigate whether Dnmt1 may have an underappreciated role in plasticity in behaviour.
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Affiliation(s)
- Emily C. Wright
- Department of Psychology, University of California, Davis, CA, USA
| | - Sarah A. Johnson
- Bond Life Science Center, Department of Biomedical Sciences, Department of Animal Science, University of Missouri, Columbia, MO, USA
| | - Rebecca Hao
- Department of Psychology, University of California, Davis, CA, USA
| | | | - Gian D. Greenberg
- Neuroscience Graduate Group, University of California, Davis, CA, USA
| | | | | | - Brian C. Trainor
- Department of Psychology, University of California, Davis, CA, USA
- Neuroscience Graduate Group, University of California, Davis, CA, USA
| | - Cheryl S. Rosenfeld
- Bond Life Science Center, Department of Biomedical Sciences, Department of Animal Science, University of Missouri, Columbia, MO, USA
- Genetics Area Program and Thompson Center for Autism and Neurobehavioral Disorders, University of Missouri, Columbia, MO, USA
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24
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Patisaul HB. Endocrine disruption by dietary phyto-oestrogens: impact on dimorphic sexual systems and behaviours. Proc Nutr Soc 2017; 76:130-144. [PMID: 27389644 PMCID: PMC5646220 DOI: 10.1017/s0029665116000677] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A wide range of health benefits have been ascribed to soya intake including a lowered risk of osteoporosis, heart disease, breast cancer, and menopausal symptoms. Because it is a hormonally active diet, however, soya can also be endocrine disrupting, suggesting that intake has the potential to cause adverse health effects in certain circumstances, particularly when exposure occurs during development. Consequently, the question of whether or not soya phyto-oestrogens are beneficial or harmful to human health is neither straightforward nor universally applicable to all groups. Possible benefits and risks depend on age, health status, and even the presence or absence of specific gut microflora. As global consumption increases, greater awareness and consideration of the endocrine-disrupting properties of soya by nutrition specialists and other health practitioners is needed. Consumption by infants and small children is of particular concern because their hormone-sensitive organs, including the brain and reproductive system, are still undergoing sexual differentiation and maturation. Thus, their susceptibility to the endocrine-disrupting activities of soya phyto-oestrogens may be especially high. As oestrogen receptor partial agonists with molecular and cellular properties similar to anthropogenic endocrine disruptors such as bisphenol A, the soya phyto-oestrogens provide an interesting model for how attitudes about what is 'synthetic' v. what is 'natural,' shapes understanding and perception of what it means for a compound to be endocrine disrupting and/or potentially harmful. This review describes the endocrine-disrupting properties of soya phyto-oestrogens with a focus on neuroendocrine development and behaviour.
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Affiliation(s)
- Heather B Patisaul
- Department of Biological Sciences,Center for Human Health and the Environment,NC State University,Raleigh,NC 27695,USA
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25
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Stephens SBZ, Kauffman AS. Regulation and Possible Functions of Kisspeptin in the Medial Amygdala. Front Endocrinol (Lausanne) 2017; 8:191. [PMID: 28824550 PMCID: PMC5545938 DOI: 10.3389/fendo.2017.00191] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
Abstract
Kisspeptin, encoded by the Kiss1 gene, is required for reproduction. Humans and mice lacking kisspeptin or its receptor, Kiss1r, have impairments in reproductive physiology and fertility. In addition to being located in the hypothalamus in the anteroventral periventricular and arcuate nuclei, kisspeptin neurons are also present in several extra-hypothalamic regions, such as the medial amygdala (MeA). However, while there has been a significant focus on the reproductive roles of hypothalamic kisspeptin neurons, the regulation and function(s) of MeA and other extra-hypothalamic kisspeptin neurons have received far less attention. This review summarizes what is currently known about the regulation, development, neural projections, and potential functions of MeA kisspeptin neurons, as well as kisspeptin signaling directly within the MeA, with emphasis on data gathered from rodent models. Recent data are summarized and compared between rodent species and also between males and females. In addition, critical gaps in knowledge and important future directions are discussed.
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Affiliation(s)
- Shannon B. Z. Stephens
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Alexander S. Kauffman
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, CA, United States
- *Correspondence: Alexander S. Kauffman,
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Stephens SBZ, Chahal N, Munaganuru N, Parra RA, Kauffman AS. Estrogen Stimulation of Kiss1 Expression in the Medial Amygdala Involves Estrogen Receptor-α But Not Estrogen Receptor-β. Endocrinology 2016; 157:4021-4031. [PMID: 27564649 PMCID: PMC5045512 DOI: 10.1210/en.2016-1431] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The neuropeptide kisspeptin, encoded by Kiss1, regulates reproduction by stimulating GnRH secretion. Neurons synthesizing kisspeptin are predominantly located in the hypothalamic anteroventral periventricular (AVPV) and arcuate nuclei, but smaller kisspeptin neuronal populations also reside in extrahypothalamic brain regions, such as the medial amygdala (MeA). In adult rodents, estradiol (E2) increases Kiss1 expression in the MeA, as in the AVPV. However, unlike AVPV and arcuate nuclei kisspeptin neurons, little else is currently known about the development, regulation, and function of MeA Kiss1 neurons. We first assessed the developmental onset of MeA Kiss1 expression in males and found that MeA Kiss1 expression is absent at juvenile ages but significantly increases during the late pubertal period, around postnatal day 35, coincident with increases in circulating sex steroids. We next tested whether developmental MeA Kiss1 expression could be induced early by E2 exposure prior to puberty. We found that juvenile mice given short-term E2 had greatly increased MeA Kiss1 expression at postnatal day 18. Although MeA Kiss1 neurons are known to be E2 up-regulated, the specific estrogen receptor (ER) pathway(s) mediating this stimulation are unknown. Using adult ERα knockout and ERβ knockout mice, we next determined that ERα, but not ERβ, is required for maximal E2-induced MeA Kiss1 expression in both sexes. These results delineate both the developmental time course of MeA Kiss1 expression and the specific ER signaling pathway required for E2-induced up-regulation of Kiss1 in this extrahypothalamic brain region. These findings will help drive future studies ascertaining the potential functions of this understudied kisspeptin population.
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Affiliation(s)
- Shannon B Z Stephens
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093
| | - Navdeep Chahal
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093
| | - Nagambika Munaganuru
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093
| | - Ruby A Parra
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093
| | - Alexander S Kauffman
- Department of Reproductive Medicine, University of California, San Diego, La Jolla, California 92093
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27
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Sex differences in the brain–an interplay of sex steroid hormones and sex chromosomes. Clin Sci (Lond) 2016; 130:1481-97. [DOI: 10.1042/cs20160299] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/17/2016] [Indexed: 12/12/2022]
Abstract
Although considerable progress has been made in our understanding of brain function, many questions remain unanswered. The ultimate goal of studying the brain is to understand the connection between brain structure and function and behavioural outcomes. Since sex differences in brain morphology were first observed, subsequent studies suggest different functional organization of the male and female brains in humans. Sex and gender have been identified as being a significant factor in understanding human physiology, health and disease, and the biological differences between the sexes is not limited to the gonads and secondary sexual characteristics, but also affects the structure and, more crucially, the function of the brain and other organs. Significant variability in brain structures between individuals, in addition to between the sexes, is factor that complicates the study of sex differences in the brain. In this review, we explore the current understanding of sex differences in the brain, mostly focusing on preclinical animal studies.
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Liu X, Herbison AE. Kisspeptin Regulation of Neuronal Activity throughout the Central Nervous System. Endocrinol Metab (Seoul) 2016; 31:193-205. [PMID: 27246282 PMCID: PMC4923402 DOI: 10.3803/enm.2016.31.2.193] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 04/14/2016] [Accepted: 04/22/2016] [Indexed: 12/30/2022] Open
Abstract
Kisspeptin signaling at the gonadotropin-releasing hormone (GnRH) neuron is now relatively well characterized and established as being critical for the neural control of fertility. However, kisspeptin fibers and the kisspeptin receptor (KISS1R) are detected throughout the brain suggesting that kisspeptin is involved in regulating the activity of multiple neuronal circuits. We provide here a review of kisspeptin actions on neuronal populations throughout the brain including the magnocellular oxytocin and vasopressin neurons, and cells within the arcuate nucleus, hippocampus, and amygdala. The actions of kisspeptin in these brain regions are compared to its effects upon GnRH neurons. Two major themes arise from this analysis. First, it is apparent that kisspeptin signaling through KISS1R at the GnRH neuron is a unique, extremely potent form or neurotransmission whereas kisspeptin actions through KISS1R in other brain regions exhibit neuromodulatory actions typical of other neuropeptides. Second, it is becoming increasingly likely that kisspeptin acts as a neuromodulator not only through KISS1R but also through other RFamide receptors such as the neuropeptide FF receptors (NPFFRs). We suggest likely locations of kisspeptin signaling through NPFFRs but note that only limited tools are presently available for examining kisspeptin cross-signaling within the RFamide family of neuropeptides.
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Affiliation(s)
- Xinhuai Liu
- Centre for Neuroendocrinology, Department of Physiology, University of Otago School of Medical Sciences, Dunedin, New Zealand
| | - Allan E Herbison
- Centre for Neuroendocrinology, Department of Physiology, University of Otago School of Medical Sciences, Dunedin, New Zealand.
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29
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Luo E, Stephens SBZ, Chaing S, Munaganuru N, Kauffman AS, Breen KM. Corticosterone Blocks Ovarian Cyclicity and the LH Surge via Decreased Kisspeptin Neuron Activation in Female Mice. Endocrinology 2016; 157:1187-99. [PMID: 26697722 PMCID: PMC4769373 DOI: 10.1210/en.2015-1711] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Stress elicits activation of the hypothalamic-pituitary-adrenal axis, which leads to enhanced circulating glucocorticoids, as well as impaired gonadotropin secretion and ovarian cyclicity. Here, we tested the hypothesis that elevated, stress-levels of glucocorticoids disrupt ovarian cyclicity by interfering with the preovulatory sequence of endocrine events necessary for the LH surge. Ovarian cyclicity was monitored in female mice implanted with a cholesterol or corticosterone (Cort) pellet. Cort, but not cholesterol, arrested cyclicity in diestrus. Subsequent studies focused on the mechanism whereby Cort stalled the preovulatory sequence by assessing responsiveness to the positive feedback estradiol signal. Ovariectomized mice were treated with an LH surge-inducing estradiol implant, as well as Cort or cholesterol, and assessed several days later for LH levels on the evening of the anticipated surge. All cholesterol females showed a clear LH surge. At the time of the anticipated surge, LH levels were undetectable in Cort-treated females. In situ hybridization analyses the anteroventral periventricular nucleus revealed that Cort robustly suppressed the percentage of Kiss1 cells coexpressing cfos, as well as reduced the number of Kiss1 cells and amount of Kiss1 mRNA per cell, compared with expression in control brains. In addition, Cort blunted pituitary expression of the genes encoding the GnRH receptor and LHβ, indicating inhibition of gonadotropes during the blockage of the LH surge. Collectively, our findings support the hypothesis that physiological stress-levels of Cort disrupts ovarian cyclicity, in part, through disruption of positive feedback mechanisms at both the hypothalamic and pituitary levels which are necessary for generation of the preovulatory LH surge.
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Affiliation(s)
- Elena Luo
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
| | - Shannon B Z Stephens
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
| | - Sharon Chaing
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
| | - Nagambika Munaganuru
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
| | - Alexander S Kauffman
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
| | - Kellie M Breen
- Department of Reproductive Medicine and Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California 92093-0674
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30
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Cisternas CD, Tome K, Caeiro XE, Dadam FM, Garcia-Segura LM, Cambiasso MJ. Sex chromosome complement determines sex differences in aromatase expression and regulation in the stria terminalis and anterior amygdala of the developing mouse brain. Mol Cell Endocrinol 2015; 414:99-110. [PMID: 26231585 DOI: 10.1016/j.mce.2015.07.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/24/2015] [Accepted: 07/25/2015] [Indexed: 10/23/2022]
Abstract
Aromatase, which converts testosterone in estradiol, is involved in the generation of brain sex dimorphisms. Here we used the "four core genotypes" mouse model, in which the effect of gonadal sex and sex chromosome complement is dissociated, to determine if sex chromosomes influence the expression of brain aromatase. The brain of 16 days old XY mouse embryos showed higher aromatase expression in the stria terminalis and the anterior amygdaloid area than the brain of XX embryos, independent of gonadal sex. Furthermore, estradiol or dihydrotestosterone increased aromatase expression in cultures of anterior amygdala neurons derived from XX embryos, but not in those derived from XY embryos. This effect was also independent of gonadal sex. The expression of other steroidogenic molecules, estrogen receptor-α and androgen receptor was not influenced by sex chromosomes. In conclusion, sex chromosomes determine sex dimorphisms in aromatase expression and regulation in the developing mouse brain.
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Affiliation(s)
- Carla D Cisternas
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Karina Tome
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Ximena E Caeiro
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Florencia M Dadam
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina
| | | | - María J Cambiasso
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC-CONICET-Universidad Nacional de Córdoba, Córdoba, Argentina; Departamento de Biología Bucal, Facultad de Odontología - Universidad Nacional de Córdoba, Córdoba, Argentina.
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31
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Li XF, Hu MH, Hanley BP, Lin YS, Poston L, Lightman SL, O'Byrne KT. The Posterodorsal Medial Amygdala Regulates the Timing of Puberty Onset in Female Rats. Endocrinology 2015; 156:3725-36. [PMID: 26252061 PMCID: PMC4588820 DOI: 10.1210/en.2015-1366] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Obesity is the major risk factor for early puberty, but emerging evidence indicates other factors including psychosocial stress. One key brain region notable for its role in controlling calorie intake, stress, and behavior is the amygdala. Early studies involving amygdala lesions that included the medial nucleus advanced puberty in rats. More recently it was shown that a critical site for lesion-induced hyperphagia and obesity is the posterodorsal subnucleus of the medial amygdala (MePD), which may explain the advancement of puberty. Glutamatergic activity also increases in the MePD during puberty without a corresponding γ-aminobutyric acid (GABA)ergic change, suggesting an overall activation of this brain region. In the present study, we report that neurotoxic lesioning of the MePD advances puberty and increases weight gain in female rats fed a normal diet. However, MePD lesioned rats fed a 25% nonnutritive bulk diet also showed the dramatic advancement of puberty but without the increase in body weight. In both dietary groups, MePD lesions resulted in an increase in socialization and a decrease in play fighting behavior. Chronic GABAA receptor antagonism in the MePD from postnatal day 21 for 14 days also advanced puberty, increased socialization, and decreased play fighting without altering body weight, whereas glutamate receptor antagonism delayed puberty and decreased socialization without affecting play fighting. In conclusion, our results suggest the MePD regulates the timing of puberty via a novel mechanism independent of change in body weight and caloric intake. MePD glutamatergic systems advance the timing of puberty whereas local GABAergic activation results in a delay.
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Affiliation(s)
- X F Li
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - M H Hu
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - B P Hanley
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - Y S Lin
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - L Poston
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - S L Lightman
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
| | - K T O'Byrne
- Division of Women's Health (X.F.L., M.H.L., B.P.H., Y.S.L., L.P., K.T.O.), Faculty of Life Sciences and Medicine, King's College London, Guy's Campus, London SE1 1UL, United Kingdom; and Henry Wellcome Laboratory for Integrative Neuroscience and Endocrinology (S.L.L.), University of Bristol, Bristol BS1 3NY, United Kingdom
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32
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Ploskonka SD, Eaton JL, Carr MS, Schmidt JV, Cushing BS. Developmental expression of estrogen receptor beta in the brain of prairie voles (Microtus ochrogaster). Dev Psychobiol 2015; 58:223-30. [PMID: 26419697 DOI: 10.1002/dev.21367] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 09/18/2015] [Indexed: 12/29/2022]
Abstract
Here, for the first time, the expression of estrogen receptor beta (ERβ) is characterized in the brains of the highly prosocial prairie vole (Microtus ochrogaster). ERβ immunoreactivity was compared in weanlings (postnatal Day 21) and adult males and females. The results indicate several major findings. First, unlike ERα, ERβ expression is not sexually dimorphic. Second, the adult pattern of ERβ-IR is established at the time of weaning, as there were no age-dependent effects on distribution. Finally, ERβ does not appear to be as widely distributed in voles compared with rats and mice. High levels of ERβ-IR were observed in several regions/nuclei within the medial pre-optic area, ventrolateral pre-optic nuclei, and in the hypothalamus, especially in the paraventricular and supraoptic nuclei. The visualization of ERβ in prairie voles is important as the socially monogamous prairie vole functions as a human relevant model system for studying the expression of social behavior and social deficit disorders. Future studies will now be able to determine the effect of treatments on the expression and/or development of ERβ in this highly social species.
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Affiliation(s)
- Stephanie D Ploskonka
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH, 44325
| | - Jennifer L Eaton
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH, 44325
| | - Michael S Carr
- Department of Biological Sciences, University of Illinois Chicago, Chicago, IL, 60607
| | - Jennifer V Schmidt
- Department of Biological Sciences, University of Illinois Chicago, Chicago, IL, 60607
| | - Bruce S Cushing
- Department of Biology and Integrated Bioscience Program, The University of Akron, Akron, OH, 44325. .,Department of Biological Sciences, The University of Texas at El Paso, El Paso, TX, 79968.
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33
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Piet R, de Croft S, Liu X, Herbison AE. Electrical properties of kisspeptin neurons and their regulation of GnRH neurons. Front Neuroendocrinol 2015; 36:15-27. [PMID: 24907402 DOI: 10.1016/j.yfrne.2014.05.006] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 04/01/2014] [Accepted: 05/27/2014] [Indexed: 01/19/2023]
Abstract
Kisspeptin neurons are critical components of the neuronal network controlling the activity of the gonadotropin-releasing hormone (GnRH) neurons. A variety of genetically-manipulated mouse models have recently facilitated the study of the electrical activity of the two principal kisspeptin neuron populations located in the rostral periventricular area of the third ventricle (RP3V) and arcuate nucleus (ARN) in acute brain slices. We discuss here the mechanisms and pathways through which kisspeptin neurons regulate GnRH neuron activity. We then examine the different kisspeptin-green fluorescent protein mouse models being used for kisspeptin electrophysiology and the data obtained to date for RP3V and ARN kisspeptin neurons. In light of these new observations on the spontaneous firing rates, intrinsic membrane properties, and neurotransmitter regulation of kisspeptin neurons, we speculate on the physiological roles of the different kisspeptin populations.
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Affiliation(s)
- Richard Piet
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Simon de Croft
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Xinhuai Liu
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand
| | - Allan E Herbison
- Centre for Neuroendocrinology and Department of Physiology, Otago School of Medical Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
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Fokidis HB, Adomat HH, Kharmate G, Hosseini-Beheshti E, Guns ES, Soma KK. Regulation of local steroidogenesis in the brain and in prostate cancer: lessons learned from interdisciplinary collaboration. Front Neuroendocrinol 2015; 36:108-29. [PMID: 25223867 DOI: 10.1016/j.yfrne.2014.08.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 08/28/2014] [Accepted: 08/28/2014] [Indexed: 11/16/2022]
Abstract
Sex steroids play critical roles in the regulation of the brain and many other organs. Traditionally, researchers have focused on sex steroid signaling that involves travel from the gonads via the circulation to intracellular receptors in target tissues. This classic concept has been challenged, however, by the growing number of cases in which steroids are synthesized locally and act locally within diverse tissues. For example, the brain and prostate carcinoma were previously considered targets of gonadal sex steroids, but under certain circumstances, these tissues can upregulate their steroidogenic potential, particularly when circulating sex steroid concentrations are low. We review some of the similarities and differences between local sex steroid synthesis in the brain and prostate cancer. We also share five lessons that we have learned during the course of our interdisciplinary collaboration, which brought together neuroendocrinologists and cancer biologists. These lessons have important implications for future research in both fields.
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Affiliation(s)
- H Bobby Fokidis
- Department of Biology, Rollins College, Winter Park, FL 37289, USA; Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada.
| | - Hans H Adomat
- Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada
| | | | | | - Emma S Guns
- Vancouver Prostate Centre, Vancouver, BC V6H 3Z6, Canada; Department of Urological Sciences, University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Kiran K Soma
- Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Brain Research Centre, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Zoology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
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35
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Akhmadeev AV, Kalimullina LB. Paleoamygdala: morphogenesis of the posterior cortical nucleus of the rat amygdaloid complex of the brain during the early juvenile period. Bull Exp Biol Med 2014; 157:645-8. [PMID: 25257432 DOI: 10.1007/s10517-014-2635-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Indexed: 10/24/2022]
Abstract
Sex-related differences and the dynamic of formation of the posterior cortical nucleus of the rat amygdaloid complex were revealed in the early juvenile period by planimetric characteristics, numbers of neurons and glial cells, and glial and apoptotic indexes reflecting morphological restructuring on postnatal days 21, 24, 28, and 31.
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Affiliation(s)
- A V Akhmadeev
- Department of Human and Animal Morphology and Physiology, Bashkir State University, Ufa, Russia,
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36
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Rebuli ME, Cao J, Sluzas E, Delclos KB, Camacho L, Lewis SM, Vanlandingham MM, Patisaul HB. Investigation of the effects of subchronic low dose oral exposure to bisphenol A (BPA) and ethinyl estradiol (EE) on estrogen receptor expression in the juvenile and adult female rat hypothalamus. Toxicol Sci 2014; 140:190-203. [PMID: 24752507 DOI: 10.1093/toxsci/kfu074] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Concerns have been raised regarding the long-term impacts of early life exposure to the ubiquitous environmental contaminant bisphenol A (BPA) on brain organization. Because BPA has been reported to affect estrogen signaling, and steroid hormones play a critical role in brain sexual differentiation, there is also concern that BPA exposure could alter neural sex differences. Here, we examine the impact of subchronic exposure from gestation to adulthood to oral doses of BPA below the current no-observed-adverse-effect level (NOAEL) of 5 mg/kg body weight (bw)/day on estrogen receptor (ESR) expression in sexually dimorphic brain regions of prepubertal and adult female rats. The dams were gavaged daily with vehicle (0.3% carboxymethylcellulose), 2.5, 25, 260, or 2700 μg BPA/kg bw/day, or 0.5 or 5.0 μg ethinyl estradiol (EE)/kg bw/day from gestational day 6 until labor began. Offspring were then gavaged directly from the day after birth until the day before scheduled sacrifice on postnatal days 21 or 90. Using in situ hybridization, one or more BPA doses produced significant decreases in Esr1 expression in the juvenile female rat anteroventral periventricular nucleus (AVPV) of the hypothalamus and significant decreases in Esr2 expression in the adult female rat AVPV and medial preoptic area (MPOA), relative to vehicle controls. BPA did not simply reproduce EE effects, indicating that BPA is not acting solely as an estrogen mimic. The possible consequences of long-term changes in hypothalamic ESR expression resulting from subchronic low dose BPA exposure on neuroendocrine effects are discussed and being addressed in ongoing, related work.
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Affiliation(s)
- Meghan E Rebuli
- Department of Biology, North Carolina State University, Raleigh, North Carolina 27695 Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Jinyan Cao
- Department of Biology, North Carolina State University, Raleigh, North Carolina 27695 Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - Emily Sluzas
- Department of Biology, North Carolina State University, Raleigh, North Carolina 27695
| | - K Barry Delclos
- National Center for Toxicological Research, Jefferson, Arkansas 72079
| | - Luísa Camacho
- National Center for Toxicological Research, Jefferson, Arkansas 72079
| | - Sherry M Lewis
- National Center for Toxicological Research, Jefferson, Arkansas 72079
| | | | - Heather B Patisaul
- Department of Biology, North Carolina State University, Raleigh, North Carolina 27695 Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695
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37
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Cao J, Joyner L, Mickens JA, Leyrer SM, Patisaul HB. Sex-specific Esr2 mRNA expression in the rat hypothalamus and amygdala is altered by neonatal bisphenol A exposure. Reproduction 2014; 147:537-54. [PMID: 24352099 PMCID: PMC3947720 DOI: 10.1530/rep-13-0501] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Perinatal life is a critical window for sexually dimorphic brain organization, and profoundly influenced by steroid hormones. Exposure to endocrine-disrupting compounds may disrupt this process, resulting in compromised reproductive physiology and behavior. To test the hypothesis that neonatal bisphenol A (BPA) exposure can alter sex-specific postnatal Esr2 (Erβ) expression in brain regions fundamental to sociosexual behavior, we mapped Esr2 mRNA levels in the principal nucleus of the bed nucleus of the stria terminalis (BNSTp), paraventricular nucleus (PVN), anterior portion of the medial amygdaloid nucleus (MeA), super optic nucleus, suprachiasmatic nucleus, and lateral habenula across postnatal days (PNDs) 0-19. Next, rat pups of both sexes were subcutaneously injected with 10 μg estradiol benzoate (EB), 50 μg/kg BPA (LBPA), or 50 mg/kg BPA (HBPA) over the first 3 days of life and Esr2 levels were quantified in each region of interest (ROI) on PNDs 4 and 10. EB exposure decreased Esr2 signal in most female ROIs and in the male PVN. In the BNSTp, Esr2 expression decreased in LBPA males and HBPA females on PND 10, thereby reversing the sex difference in expression. In the PVN, Esr2 mRNA levels were elevated in LBPA females, also resulting in a reversal of sexually dimorphic expression. In the MeA, BPA decreased Esr2 expression on PND 4. Collectively, these data demonstrate that region- and sex-specific Esr2 expression is vulnerable to neonatal BPA exposure in regions of the developing brain critical to sociosexual behavior in rat.
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Affiliation(s)
- Jinyan Cao
- Department of Biology, NCSU, Raleigh NC, 27695
| | | | | | | | - Heather B Patisaul
- Department of Biology, NCSU, Raleigh NC, 27695
- Keck Center for Behavioral Biology, NCSU, Raleigh NC, 27695
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Di Giorgio NP, Semaan SJ, Kim J, López PV, Bettler B, Libertun C, Lux-Lantos VA, Kauffman AS. Impaired GABAB receptor signaling dramatically up-regulates Kiss1 expression selectively in nonhypothalamic brain regions of adult but not prepubertal mice. Endocrinology 2014; 155:1033-44. [PMID: 24424047 PMCID: PMC3929734 DOI: 10.1210/en.2013-1573] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Kisspeptin, encoded by Kiss1, stimulates reproduction and is synthesized in the hypothalamic anteroventral periventricular and arcuate nuclei. Kiss1 is also expressed at lower levels in the medial amygdala (MeA) and bed nucleus of the stria terminalis (BNST), but the regulation and function of Kiss1 there is poorly understood. γ-Aminobutyric acid (GABA) also regulates reproduction, and female GABAB1 receptor knockout (KO) mice have compromised fertility. However, the interaction between GABAB receptors and Kiss1 neurons is unknown. Here, using double-label in situ hybridization, we first demonstrated that a majority of hypothalamic Kiss1 neurons coexpress GABAB1 subunit, a finding also confirmed for most MeA Kiss1 neurons. Yet, despite known reproductive impairments in GABAB1KO mice, Kiss1 expression in the anteroventral periventricular and arcuate nuclei, assessed by both in situ hybridization and real-time PCR, was identical between adult wild-type and GABAB1KO mice. Surprisingly, however, Kiss1 levels in the BNST and MeA, as well as the lateral septum (a region normally lacking Kiss1 expression), were dramatically increased in both GABAB1KO males and females. The increased Kiss1 levels in extrahypothalamic regions were not caused by elevated sex steroids (which can increase Kiss1 expression), because circulating estradiol and testosterone were equivalent between genotypes. Interestingly, increased Kiss1 expression was not detected in the MeA or BNST in prepubertal KO mice of either sex, indicating that the enhancements in extrahypothalamic Kiss1 levels initiate during/after puberty. These findings suggest that GABAB signaling may normally directly or indirectly inhibit Kiss1 expression, particularly in the BNST and MeA, and highlight the importance of studying kisspeptin populations outside the hypothalamus.
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Affiliation(s)
- Noelia P Di Giorgio
- Institute of Biology and Experimental Medicine-CONICET (N.P.D.G., P.V.L., C.L., V.A.L-L.), Buenos Aires, Argentina; Department of Reproductive Medicine (S.J.S., J.K., A.S.K.), University of California San Diego, La Jolla, California; Department of Biomedicine (B.B.), University of Basel, Basel, Switzerland; and Department of Physiology (C.L.), University of Buenos Aires, Buenos Aires, Argentina
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Immunolocalization of Kisspeptin Associated with Amyloid-β Deposits in the Pons of an Alzheimer's Disease Patient. JOURNAL OF NEURODEGENERATIVE DISEASES 2013; 2013:879710. [PMID: 26317001 PMCID: PMC4437339 DOI: 10.1155/2013/879710] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Revised: 04/23/2013] [Accepted: 04/24/2013] [Indexed: 02/03/2023]
Abstract
The pons region of the Alzheimer's disease (AD) brain is one of the last to show amyloid-β (Aβ) deposits and has been suggested to contain neuroprotective compounds. Kisspeptin (KP) is a hormone that activates the hypothalamic-pituitary-gonadal axis and has been suggested to be neuroprotective against Aβ toxicity. The localization of KP, plus the established endogenous neuroprotective compounds corticotropin releasing hormone (CRH) and catalase, in tissue sections from the pons region of a male AD subject has been determined in relation to Aβ deposits. Results showed Aβ deposits also stained with KP, CRH, and catalase antibodies. At high magnification the staining of deposits was either KP or catalase positive, and there was only a limited area of the deposits with KP-catalase colocalization. The CRH does not bind Aβ, whilst both KP and catalase can bind Aβ, suggesting that colocalization in Aβ deposits is not restricted to compounds that directly bind Aβ. The neuroprotective actions of KP, CRH, and catalase were confirmed in vitro, and fibrillar Aβ preparations were shown to stimulate the release of KP in vitro. In conclusion, neuroprotective KP, CRH, and catalase all colocalize with Aβ plaque-like deposits in the pons region from a male AD subject.
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Cao J, Rebuli ME, Rogers J, Todd KL, Leyrer SM, Ferguson SA, Patisaul HB. Prenatal bisphenol A exposure alters sex-specific estrogen receptor expression in the neonatal rat hypothalamus and amygdala. Toxicol Sci 2013; 133:157-73. [PMID: 23457122 DOI: 10.1093/toxsci/kft035] [Citation(s) in RCA: 112] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Bisphenol A (BPA) exposure is ubiquitous, and in laboratory animals, early-life BPA exposure has been shown to alter sex-specific neural organization, neuroendocrine physiology, and behavior. The specific mechanisms underlying these brain-related outcomes, however, remain largely unknown, constraining the capacity to ascertain the potential human relevance of neural effects observed in animal models. In the perinatal rat brain, estrogen is masculinizing, suggesting that BPA-induced perturbation of estrogen receptor (ESR) expression may underpin later in-life neuroendocrine effects. We hypothesized that prenatal BPA exposure alters sex-specific ESR1 (ERα) and ESR2 (ERβ) expression in postnatal limbic nuclei. Sprague Dawley rats were mated and gavaged on gestational days (GDs) 6-21 with vehicle, 2.5 or 25 μg/kg bw/day BPA, or 5 or 10 μg/kg bw/day ethinyl estradiol. An additional group was restrained but not gavaged (naïve control). Offspring were sacrificed the day after birth to quantify ESR gene expression throughout the hypothalamus and amygdala by in situ hybridization. Relative to the vehicle group, significant effects of BPA were observed on ESR1 and ESR2 expression throughout the mediobasal hypothalamus and amygdala in both sexes. Significant differences in ESR expression were also observed in the mediobasal hypothalamus and amygdala of the naïve control group compared with the vehicle group, highlighting the potential for gavage to influence gene expression in the developing brain. These results indicate that ESR expression in the neonatal brain of both sexes can be altered by low-dose prenatal BPA exposure.
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Affiliation(s)
- Jinyan Cao
- Department of Biology, NCSU, Raleigh, North Carolina 27695, USA
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