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Achterberg EJM, Burke CJ, Pellis SM. When the individual comes into play: The role of self and the partner in the dyadic play fighting of rats. Behav Processes 2023; 212:104933. [PMID: 37643663 DOI: 10.1016/j.beproc.2023.104933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 08/11/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023]
Abstract
Social play in rats is rewarding and important for the development of brain and social skills. There are differences in the amount of play behavior displayed among individuals, with earlier studies suggesting that, despite variation across trials, individual differences tend to be consistent. In the present study, juvenile Lister-hooded rats were paired with a different, unfamiliar same-sex partner on three days and based on the amount of play each individual initiated, it was characterized as a high, medium or low player. Using this categorization, we explored three features related to individual differences. First, we show that by increasing the number of test days from two, as was done in a previous study (Lesscher et al., 2021), to three, characterization was effectively improved. Secondly, while the earlier study only used males, the present study showed that both sexes exhibit a similar pattern of individual differences in the degree of playfulness. Even though low players consistently initiated less play than medium and high players, all rats varied in how much play they initiated from one trial to the next. Thirdly, we assessed two potential mechanisms by which the playfulness of one rat can modify the level of playfulness of the other rat (i.e., emotional contagion vs homeostasis). Analyses of individuals' contribution to the play of dyads suggest that rats consistently adjust their play behavior depending on the behavior displayed by the partner. Since this adjustment can be positive or negative, our data support a homeostatic mechanism, whereby individuals increase or decrease the amount of play they initiate, which results in the experience of an overall stable pattern of play across trials. Future research will investigate the neural bases for individual differences in play and how rats maintain a preferred level of play.
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Affiliation(s)
- E J M Achterberg
- Behavioural Neuroscience Division, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
| | - C J Burke
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada; Department of Pharmacology, McGill University, Montreal, Canada
| | - S M Pellis
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
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2
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McCarthy MM. Neural Control of Sexually Dimorphic Social Behavior: Connecting Development to Adulthood. Annu Rev Neurosci 2023; 46:321-339. [PMID: 37001242 DOI: 10.1146/annurev-neuro-121522-110856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Rapid advances in the neural control of social behavior highlight the role of interconnected nodes engaged in differential information processing to generate behavior. Many innate social behaviors are essential to reproductive fitness and therefore fundamentally different in males and females. Programming these differences occurs early in development in mammals, following gonadal differentiation and copious androgen production by the fetal testis during a critical period. Early-life programming of social behavior and its adult manifestation are separate but yoked processes, yet how they are linked is unknown. This review seeks to highlight that gap by identifying four core mechanisms (epigenetics, cell death, circuit formation, and adult hormonal modulation) that could connect developmental changes to the adult behaviors of mating and aggression. We further propose that a unique social behavior, adolescent play, bridges the preweaning to the postpubertal brain by engaging the same neural networks underpinning adult reproductive and aggressive behaviors.
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Affiliation(s)
- Margaret M McCarthy
- Department of Pharmacology and Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, USA;
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3
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Pellis SM, Pellis VC, Burke CJ, Stark RA, Ham JR, Euston DR, Achterberg EJM. Measuring Play Fighting in Rats: A Multilayered Approach. Curr Protoc 2022; 2:e337. [PMID: 35030300 DOI: 10.1002/cpz1.337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Rough-and-tumble play or play fighting is an important experience in the juvenile period of many species of mammals, as it facilitates the development of social skills, and for some species, play fighting is retained into adulthood as a tool for assessing and managing social relationships. Laboratory rats have been a model species for studying the neurobiology of play fighting and its key developmental and social functions. However, play fighting interactions are complex, involving competition and cooperation; therefore, no single measure to quantify this behavior is able to capture all its facets. Therefore, in this paper, we present a multilayered framework for scoring all the relevant facets of play that can be affected by experimental manipulations and the logic of how to match what is measured with the question being asked. © 2022 Wiley Periodicals LLC.
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Affiliation(s)
- S M Pellis
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - V C Pellis
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - C J Burke
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - R A Stark
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - J R Ham
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - D R Euston
- Department of Neuroscience, University of Lethbridge, Lethbridge, Canada
| | - E J M Achterberg
- Division Behavioural Neuroscience, Unit Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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4
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Vitor-Vieira F, Vilela FC, Giusti-Paiva A. Hyperactivation of the amygdala correlates with impaired social play behavior of prepubertal male rats in a maternal immune activation model. Behav Brain Res 2021; 414:113503. [PMID: 34331970 DOI: 10.1016/j.bbr.2021.113503] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 07/12/2021] [Accepted: 07/26/2021] [Indexed: 12/17/2022]
Abstract
Maternal infection during pregnancy is an environmental risk factor for neurodevelopmental dysfunction, such as autism spectrum disorder (ASD). This study investigated the effect of maternal immune activation (MIA) on the behavior profile of prepubertal offspring and whether MIA alters the neuronal activation pattern of brain areas related to social play behavior. Pregnant Wistar rats received 500 μg/kg of lipopolysaccharide or saline solution on gestational day 16. Their offspring were tested using behavioral tasks to capture some of the core and associated ASD-like symptoms. Neuronal activation, indexed via c-fos expression after social play behavior, was evaluated in several brain areas. MIA had a number of adverse effects on dams and reduced the number of successful births and litter size. MIA induced sex-specific autistic-like features by a reduction in ultrasonic vocalizations in response to separation from the mother and nest, reduction in discrimination between neutral odors and their nest odor, moderate effect in stereotypies in the hole-board test, impaired risk assessment phenotype, and reduction in social play behavior without changes in locomotor activity only in prepubertal male offspring. A decrease in social play behavior may be associated with a decrease in the number of c-fos-positive cells in the prefrontal cortex and striatum, but hyperactivation of the basolateral and basomedial amygdala. Prenatal immune challenge results in ASD-like symptoms such as impaired risk assessment behavior, communication, and social interactions in male prepubertal offspring. Impaired social play behavior is correlated with neuronal hyperactivation in the amygdala.
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Affiliation(s)
- Fernando Vitor-Vieira
- Department of Physiological Sciences, Institute of Biomedical Sciences, Federal University of Alfenas-MG, Alfenas, Brazil
| | - Fabiana C Vilela
- Department of Physiological Sciences, Institute of Biomedical Sciences, Federal University of Alfenas-MG, Alfenas, Brazil
| | - Alexandre Giusti-Paiva
- Department of Physiological Sciences, Institute of Biomedical Sciences, Federal University of Alfenas-MG, Alfenas, Brazil.
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5
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VanRyzin JW, Marquardt AE, McCarthy MM. Developmental origins of sex differences in the neural circuitry of play. INTERNATIONAL JOURNAL OF PLAY 2020; 9:58-75. [PMID: 33717644 PMCID: PMC7954123 DOI: 10.1080/21594937.2020.1723370] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 01/24/2020] [Indexed: 06/12/2023]
Abstract
Social play consists of reciprocal physical interactions between conspecifics with many features conserved across species, including the propensity for males to engage in play more frequently and with higher physical intensity. Animal models, such as the laboratory rat, reveal that the underlying neural circuitry of play is subject to sexual differentiation during a critical period early in life. In this review, we discuss the developmental processes that produce distinct neural nodes which modulate both shared and sex-specific aspects of play with a focus on the medial amygdala, lateral septum, and prefrontal cortex. While the cellular mechanisms determining sex differences in play are beginning to be uncovered, the ultimate advantages of play continue to be debated.
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Affiliation(s)
- Jonathan W. VanRyzin
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Ashley E Marquardt
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - Margaret M McCarthy
- Department of Pharmacology, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Program in Neuroscience, University of Maryland School of Medicine, Baltimore, Maryland, United States
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6
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Zaccaroni M, Massolo A, Beani L, Seta DD, Farabollini F, Giannelli G, Fusani L, Dessì-Fulgheri F. Developmental exposure to low levels of ethinylestradiol affects social play in juvenile male rats. Toxicol Res 2020; 36:301-310. [PMID: 33005589 DOI: 10.1007/s43188-019-00035-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/21/2019] [Accepted: 11/27/2019] [Indexed: 11/29/2022] Open
Abstract
Juvenile social play contributes to the development of adult social and emotional skills in humans and non-human animals and is therefore a useful endpoint to study the effects of endocrine disrupters on behavior in animal models. Ethinylestradiol (EE2), a widely produced, powerful synthetic estrogen is widespread in the environment mainly because it is a component of the contraceptive pill. To understand whether clinical or environmental exposure to EE2 during critical perinatal periods can affect male social play, we exposed 72 male Sprague-Dawley rats to EE2 or vehicle either during gestation (from gestation day (GD) 5 through 20) or during lactation (from postnatal day (PND) 1 through 21). Two doses of EE2 were used to treat the dams: a lower dose in the range of possible environmental exposure (4 ng/kg/day) and a higher dose similar to that received during contraceptive treatment (400 ng/kg/day). Social play was observed between PND 40 and 45. A principal component analysis (PCA) of frequencies of behavioral items observed during play sessions allowed to allocate behaviors to the two main components that we named aggressive-like play and defensive-like play. Aggressive-like play was increased by gestational and decreased by lactational exposure. Defensive-like play was decreased by treatment. For both types of play the lower dose (4 ng/kg/day) was as effective as the higher one. Total social activity was increased by gestational and decreased by lactational exposure. These findings provide further evidence that exposure to low and to very low doses of EE2 during critical periods of development can affect essential aspects of social behavior, and that the timing of exposure is critical to understand its developmental action.
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Affiliation(s)
- Marco Zaccaroni
- Department di Biology, University of Firenze, Florence, Italy
| | - Alessandro Massolo
- Ethology Unit, Department of Biology, University of Pisa, Pisa, Italy and Laboratoire Chrono-environnement, Université Bourgogne Franche-Comté, Besançon, France
| | - Laura Beani
- Department di Biology, University of Firenze, Florence, Italy
| | - Daniele Della Seta
- Department of Medicine, Surgery and Neuroscience University of Siena, Siena, Italy
| | | | | | - Leonida Fusani
- Department of Cognitive Biology, University of Vienna, and Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Vienna, Austria
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Cao J, Dorris DM, Meitzen J. Electrophysiological properties of medium spiny neurons in the nucleus accumbens core of prepubertal male and female Drd1a-tdTomato line 6 BAC transgenic mice. J Neurophysiol 2018; 120:1712-1727. [PMID: 29975170 PMCID: PMC6230806 DOI: 10.1152/jn.00257.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 06/27/2018] [Accepted: 06/30/2018] [Indexed: 12/12/2022] Open
Abstract
The nucleus accumbens core (AcbC) is a striatal brain region essential for integrating motivated behavior and reward processing with premotor function. In humans and rodents, research has identified sex differences and sex steroid hormone sensitivity in AcbC-mediated behaviors, in disorders, and in rats in the electrophysiological properties of the AcbC output neuron type, the medium spiny neuron (MSN). It is unknown whether the sex differences detected in MSN electrophysiological properties extend to mice. Furthermore, MSNs come in distinct subtypes with subtle differences in electrophysiological properties, and it is unknown whether MSN subtype-specific electrophysiology varies by sex. To address these questions, we used male and female Drd1a-tdTomato line 6 bacterial artificial chromosome transgenic mice. We made acute brain slices of the AcbC, and performed whole cell patch-clamp recordings across MSN subtypes to comprehensively assess AcbC MSN subtype electrophysiological properties. We found that ( 1 mice MSNs did not exhibit the sex differences detected in rat MSNs, and 2) electrophysiological properties differed between MSN subtypes in both sexes, including rheobase, resting membrane potential, action potential properties, intrinsic excitability, input resistance in both the linear and rectified ranges, and miniature excitatory postsynaptic current properties. These findings significantly extend previous studies of MSN subtypes performed in males or animals of undetermined sex and indicate that the influence of sex upon AcbC MSN properties varies between rodent species. NEW & NOTEWORTHY This research provides the most comprehensive assessment of medium spiny neuron subtype electrophysiological properties to date in a critical brain region, the nucleus accumbens core. It additionally represents the first evaluation of whether mouse medium spiny neuron subtype electrophysiological properties differ by sex.
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Affiliation(s)
- Jinyan Cao
- Department of Biological Sciences, North Carolina State University , Raleigh, North Carolina
- W. M. Keck Center for Behavioral Biology, North Carolina State University , Raleigh, North Carolina
| | - David M Dorris
- Department of Biological Sciences, North Carolina State University , Raleigh, North Carolina
| | - John Meitzen
- Department of Biological Sciences, North Carolina State University , Raleigh, North Carolina
- W. M. Keck Center for Behavioral Biology, North Carolina State University , Raleigh, North Carolina
- Center for Human Health and the Environment, North Carolina State University , Raleigh, North Carolina
- Comparative Medicine Institute, North Carolina State University , Raleigh, North Carolina
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8
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Cafeteria diet during the gestation period programs developmental and behavioral courses in the offspring. Int J Dev Neurosci 2018; 68:45-52. [DOI: 10.1016/j.ijdevneu.2018.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 04/26/2018] [Accepted: 05/01/2018] [Indexed: 11/21/2022] Open
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9
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Warembourg C, Binter AC, Giton F, Fiet J, Labat L, Monfort C, Chevrier C, Multigner L, Cordier S, Garlantézec R. Prenatal exposure to glycol ethers and sex steroid hormones at birth. ENVIRONMENT INTERNATIONAL 2018; 113:66-73. [PMID: 29421409 DOI: 10.1016/j.envint.2018.01.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 01/15/2018] [Accepted: 01/15/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Glycol ethers (GEs) are oxygenated solvents widely found in occupational and consumer water-based products. Some of them are well-known reproductive and developmental toxicants. OBJECTIVES To study the variations in circulating sex steroid hormones, measured in cord blood, according to biomarkers of prenatal GE exposure. METHODS The study population comes from the PELAGIE mother-child cohort, which enrolled pregnant women from Brittany (France, 2002-2006). Maternal urine samples were collected from a random subcohort (n = 338) before 19 weeks' gestation, from which we measured 8 alkoxycarboxylic metabolites of GEs. We subsequently measured 13 sex steroid hormones and sex hormone-binding globulin (SHBG) in cord blood samples. Linear regressions adjusted for potential confounders were used, and nonlinear dose-response associations were investigated. RESULTS The detection rates of GE metabolites ranged from 4% to 98%; only the 5 most detected (>20%) metabolites were investigated further. Phenoxyacetic acid (detection rate > 95%) was associated with lower levels of SHBG and various steroids (17-alpha-hydroxy-Pregnenolone, delta-5-androstenediol, and dehydroepiandrosterone) among boys and higher SHBG and 16-alpha-hydroxy-dehydroepiandrosterone levels among girls. The two other highly detected metabolites, methoxyetoxyacetic acid and butoxyacetic acid, were associated with variations in estradiol. Butoxyacetic acid was associated with higher delta-5-androstenediol levels while detectable levels of methoxyacetic acid were associated with lower levels of this hormone. CONCLUSION Our study suggests that prenatal exposure to GE may affect endocrine response patterns, estimated by determining blood levels of sex steroid hormones in newborns. These results raise questions about the potential role of these changes in the pathways between prenatal GE exposure and previously reported adverse developmental outcomes, including impaired neurocognitive performance.
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Affiliation(s)
- Charline Warembourg
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France..
| | - Anne-Claire Binter
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France
| | - Frank Giton
- AP-HP, Pôle biologie-Pathologie Henri Mondor, Créteil 94000, France.; INSERM U955 eq07, Recherche Translationnelle en oncogenèse génitale, Créteil 94000, France
| | - Jean Fiet
- INSERM U955 eq07, Recherche Translationnelle en oncogenèse génitale, Créteil 94000, France
| | - Laurence Labat
- Assistance publique-hopitaux de Paris, Groupe Cochin, Laboratoire Pharmacologie Toxicologie, F-75004 Paris, France
| | - Christine Monfort
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France
| | - Cécile Chevrier
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France
| | - Luc Multigner
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France
| | - Sylvaine Cordier
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France
| | - Ronan Garlantézec
- Inserm UMR 1085 Irset, Exposure Assessment and Epidemiological Research on Environment, Reproduction and Development, F-35000 Rennes, France; Université de Rennes I, F-35043 Rennes, France.; Centre Hospitalo-Universitaire de Rennes, Service de Santé Publique et d'Epidémiologie, F-35033 Rennes, France
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10
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Kougias DG, Cortes LR, Moody L, Rhoads S, Pan YX, Juraska JM. Effects of Perinatal Exposure to Phthalates and a High-Fat Diet on Maternal Behavior and Pup Development and Social Play. Endocrinology 2018; 159:1088-1105. [PMID: 29300916 PMCID: PMC5793791 DOI: 10.1210/en.2017-03047] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 12/21/2017] [Indexed: 01/28/2023]
Abstract
Humans are ubiquitously exposed to many phthalates, a class of endocrine-disrupting chemicals commonly used in many consumer goods, and diet, especially fatty food, is presumed to be a major source of exposure. Here, we use a rat model of human prenatal exposure to investigate the potential interactive effects of an environmentally relevant mixture of phthalates and a maternal high-fat diet (HFD). From gestation through postnatal day (P)10, dams consumed the mixture of phthalates (0, 200, or 1000 μg/kg/d) and were fed a control diet or HFD. In males, perinatal exposure to the mixture of phthalates decreased prepubertal body weight and, in a dose-specific manner, periadolescent social play behavior. A dose-specific effect from phthalates with HFD was also seen in increased time alone in females during social play. HFD resulted in dams consuming more calories, having greater gestational weight gain, and licking and nursing their pups more, such that an early postnatal HFD generally increased pup body weight. There also was a tendency for increased oxidative stress markers at P10 within the medial prefrontal cortex of males exposed to the relatively high dose of phthalates and HFD. Effects on gene expression were inconsistent at P10 and P90 in both the medial prefrontal cortex and hypothalamus. Overall, this study demonstrates that phthalates and a maternal HFD only rarely interacted, except in oxidative stress markers in males. Additionally, perinatal exposure to an environmentally relevant mixture of phthalates can have a modest, but lasting, impact on social behaviors in both males and females.
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Affiliation(s)
- Daniel G. Kougias
- Neuroscience Program, University of Illinois, Champaign, Illinois 61820
| | - Laura R. Cortes
- Department of Psychology, University of Illinois, Champaign, Illinois 61820
| | - Laura Moody
- Division of Nutritional Sciences, University of Illinois, Champaign, Illinois 61820
| | - Steven Rhoads
- Department of Psychology, University of Illinois, Champaign, Illinois 61820
| | - Yuan-Xiang Pan
- Division of Nutritional Sciences, University of Illinois, Champaign, Illinois 61820
- Department of Food Science and Human Nutrition, University of Illinois, Champaign, Illinois 61820
| | - Janice M. Juraska
- Neuroscience Program, University of Illinois, Champaign, Illinois 61820
- Department of Psychology, University of Illinois, Champaign, Illinois 61820
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11
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Zaccaroni M, Massolo A, Della Seta D, Farabollini F, Giannelli G, Fusani L, Dessì-Fulgheri F. Developmental Exposure to Low Levels of Ethinylestradiol Affects Play Behavior in Juvenile Female Rats. Neurotox Res 2017; 33:876-886. [PMID: 29260494 DOI: 10.1007/s12640-017-9852-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 12/10/2017] [Accepted: 12/11/2017] [Indexed: 10/18/2022]
Abstract
Juvenile social play contributes to the development of adult social and emotional skills in humans and non-human animals, and is therefore a useful endpoint to study the effects of endocrine disrupters on behavior in animal models. Ethinylestradiol (EE2) is a widely produced, powerful synthetic estrogen that is widespread in the environment mainly because is a component of the contraceptive pill. In addition, fetuses may be exposed to EE2 when pregnancy is undetected during contraceptive treatment. To understand whether exposure to EE2 during gestation or lactation affects social play, we exposed 72 female Sprague-Dawley rats to EE2 or vehicle either during gestation (gestation day (GD) 5 through GD 20) or during lactation (from postnatal day (PND) 1 through PND 21). Two doses of EE2 were used to treat the dams: a lower dose in the range of possible environmental exposure (4 ng/kg/day) and a higher dose equivalent to that received during contraceptive treatment (400 ng/kg/day). Behavioral testing was carried out between PND 40 and 45. A principal component analysis of frequencies of behavioral items observed during play sessions identified three main components: defensive-like play, aggressive-like play, and exploration. Aggressive-like play was significantly increased by both doses of EE2, and the gestational administration was in general more effective than the lactational one. Defensive-like play and exploration were not significantly affected by treatment. This research showed that low and very low doses of EE2 that mimic clinical or environmental exposure during development can affect important aspects of social behavior even during restricted time windows.
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Affiliation(s)
- Marco Zaccaroni
- Department di Biology, University of Firenze, Florence, Italy.
| | - Alessandro Massolo
- Ethology Unit, Department of Biology, University of Pisa, Pisa, Italy.,Laboratoire Chrono-environnement, Université Bourgogne Franche-Comté, Besançon, France
| | - Daniele Della Seta
- Department of Medicine, Surgery and Neuroscience University of Siena, Siena, Italy
| | | | | | - Leonida Fusani
- Department of Cognitive Biology, University of Vienna, and Konrad Lorenz Institute for Ethology, University of Veterinary Medicine, Vienna, Austria
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12
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Early life overnutrition induced by litter size manipulation decreases social play behavior in adolescent male rats. Int J Dev Neurosci 2016; 53:75-82. [DOI: 10.1016/j.ijdevneu.2016.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/19/2016] [Accepted: 07/23/2016] [Indexed: 11/23/2022] Open
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