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Tsao CH, Wu KY, Su NC, Edwards A, Huang GJ. The influence of sex difference on behavior and adult hippocampal neurogenesis in C57BL/6 mice. Sci Rep 2023; 13:17297. [PMID: 37828065 PMCID: PMC10570284 DOI: 10.1038/s41598-023-44360-8] [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] [Received: 06/03/2023] [Accepted: 10/06/2023] [Indexed: 10/14/2023] Open
Abstract
Animal models have been used extensively in in vivo studies, especially within the biomedical field. Traditionally, single-sex studies, mostly males, are used to avoid any potential confounding variation caused by sex difference and the female estrous cycle. Historically, female animal subjects are believed to exhibit higher variability, and this could increase the statistical power needed to test a hypothesis. This study sets out to evaluate whether a sex difference does exist in mouse behavior, and whether female mice featured higher variability. We assessed the sensorimotor skills, anxiety-like behavior, depression-like behavior, and cognitive abilities of mice through a series of commonly used behavioral tests. Except for the stronger grip force and lower tactile sensory sensitivity detected in male mice, there was no significant difference between males and females in other tests. Furthermore, immunolabeling of neurogenesis markers suggested no significant difference between sexes in adult hippocampal neurogenesis. Within group variances were equivalent; females did not exhibit higher variability than males. However, the overall negative results could be due to the limitation of small sample size. In conclusion, our study provides evidence that sex difference in mice does not significantly influence these commonly used behavioral tests nor adult neurogenesis under basal conditions. We suggest that female mice could also be considered for test inclusion in future experiment design.
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Affiliation(s)
- Chi-Hui Tsao
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, 333, Taiwan
| | - Kuan-Yu Wu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, 333, Taiwan
| | - Nicole Ching Su
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, 33302, Taiwan
| | - Andrew Edwards
- Department of Psychiatry, Dykebar Hospital, National Health Service Greater Glasgow and Clyde, Paisley, PA2 7DE, Scotland
| | - Guo-Jen Huang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, 333, Taiwan.
- Department of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan, 33302, Taiwan.
- Department of Neurology, Chang Gung Memorial Hospital-Linkou Medical Center, Taoyuan, 333, Taiwan.
- Molecular Medicine Research Center, Chang Gung University, Taoyuan, 333, Taiwan.
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2
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Koszałka A, Lustyk K, Pytka K. Sex-dependent differences in animal cognition. Neurosci Biobehav Rev 2023; 153:105374. [PMID: 37634555 DOI: 10.1016/j.neubiorev.2023.105374] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/17/2023] [Accepted: 08/23/2023] [Indexed: 08/29/2023]
Abstract
The differences in cognitive processes driven by biological sex are the issues that have gotten growing attention recently. Considering the increasing population suffering from various cognitive impairments and the development of therapeutic strategies, it is essential that we recognize the mechanisms responsible for discrepancies observed in male and female learning and memory functions. In this review, we discuss recent reports from preclinical studies on rodents regarding selected cognitive domains to explore the state of knowledge on sex-dependent differences and point to challenges encountered during such research. We focus on spatial, recognition, and emotional memory, as well as on executive functions, such as attention, cognitive flexibility, and working memory. This review will help to acknowledge sex-related differences in cognition and indicate some fields that lack sufficient data.
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Affiliation(s)
- Aleksandra Koszałka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland; Jagiellonian University Medical College, Doctoral School of Medical and Health Sciences, Św. Łazarza 16, 31-530 Krakow, Poland
| | - Klaudia Lustyk
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland
| | - Karolina Pytka
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Pharmacodynamics, Medyczna 9, 30-688 Krakow, Poland.
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3
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Sex differences in fear responses: Neural circuits. Neuropharmacology 2023; 222:109298. [PMID: 36328063 DOI: 10.1016/j.neuropharm.2022.109298] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 09/26/2022] [Accepted: 10/19/2022] [Indexed: 11/06/2022]
Abstract
Women have increased vulnerability to PTSD and anxiety disorders compared to men. Understanding the neurobiological underpinnings of these disorders is critical for identifying risk factors and developing appropriate sex-specific interventions. Despite the clear clinical relevance of an examination of sex differences in fear responses, the vast majority of pre-clinical research on fear learning and memory formation has exclusively used male animals. This review highlights sex differences in context and cued fear conditioning, fear extinction and fear generalization with a focus on the neural circuits underlying these behaviors in rodents. There are mixed reports of behavioral sex differences in context and cued fear conditioning paradigms, which can depend upon the behavioral indices of fear. However, there is greater evidence of differential activation of the hippocampus, amygdalar nuclei and the prefrontal cortical regions in male and female rodents during context and cued fear conditioning. The bed nucleus of the stria terminalis (BNST), a sexually dimorphic structure, is of particular interest as it differentially contributes to fear responses in males and females. In addition, while the influence of the estrous cycle on different phases of fear conditioning is delineated, the clearest modulatory effect of estrogen is on fear extinction processes. Examining the variability in neural responses and behavior in both sexes should increase our understanding of how that variability contributes to the neurobiology of affective disorders. This article is part of the Special Issue on 'Fear, anxiety and PTSD'.
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Juraska JM. Changes in sex differences in neuroanatomical structure and cognitive behavior across the life span. Learn Mem 2022; 29:340-348. [PMID: 36206396 PMCID: PMC9488018 DOI: 10.1101/lm.053499.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 07/19/2022] [Indexed: 11/24/2022]
Abstract
Sex differences occur in the structure and function of the rat cerebral cortex and hippocampus, which can change from the juvenile period through old age. Although the evidence is incomplete, it appears that in at least some portions of the cortex these differences develop due to the rise of ovarian hormones at puberty and are potentially not dependent on the perinatal rise in testosterone, which is essential for sexual differentiation of the hypothalamus and sexual behavior. During aging of female rats, the presence of continued ovarian hormone secretion after cessation of the estrous cycle also influences sex differences in neuroanatomical structure and cognitive behavior, resulting in nullification or reversal of sex differences seen in younger adults. Sex differences can be altered by experience in a stimulating environment during the juvenile/adolescent period, and sex differences in performance even can be affected by the parameters of a task. Thus, broad generalizations about differences such as "spatial ability" are to be avoided. It is clear that to understand how the brain produces behavior, sex and hormones have to be taken into account.
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Affiliation(s)
- Janice M Juraska
- Department of Psychology, Program in Neuroscience, University of Illinois at Urbana-Champaign, Champaign, Illinois 61820, USA
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5
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Abstract
Sex and gender differences are seen in cognitive disturbances in a variety of neurological and psychiatry diseases. Men are more likely to have cognitive symptoms in schizophrenia whereas women are more likely to have more severe cognitive symptoms with major depressive disorder and Alzheimer's disease. Thus, it is important to understand sex and gender differences in underlying cognitive abilities with and without disease. Sex differences are noted in performance across various cognitive domains - with males typically outperforming females in spatial tasks and females typically outperforming males in verbal tasks. Furthermore, there are striking sex differences in brain networks that are activated during cognitive tasks and in learning strategies. Although rarely studied, there are also sex differences in the trajectory of cognitive aging. It is important to pay attention to these sex differences as they inform researchers of potential differences in resilience to age-related cognitive decline and underlying mechanisms for both healthy and pathological cognitive aging, depending on sex. We review literature on the progressive neurodegenerative disorder, Alzheimer's disease, as an example of pathological cognitive aging in which human females show greater lifetime risk, neuropathology, and cognitive impairment, compared to human males. Not surprisingly, the relationships between sex and cognition, cognitive aging, and Alzheimer's disease are nuanced and multifaceted. As such, this chapter will end with a discussion of lifestyle factors, like education and diet, as modifiable factors that can alter cognitive aging by sex. Understanding how cognition changes across age and contributing factors, like sex differences, will be essential to improving care for older adults.
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Zhvania MG, Japaridze N, Tizabi Y, Lomidze N, Pochkhidze N, Lordkipanidze T. Age-related cognitive decline in rats is sex and context dependent. Neurosci Lett 2021; 765:136262. [PMID: 34560192 DOI: 10.1016/j.neulet.2021.136262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 12/29/2022]
Abstract
Previously, we had observed age-related cognitive decline in male rats compared to adolescent and adult rats. This was shown in both a multi-branched maze test (MBM), as well as in the Morris water maze test (MWM). In the present study, we compared the behavior of similar age groups in both male and female rats using the same paradigms. The results confirmed the increase in errors and time spent in MBM in aged male rats compared to other age groups. However, no such differences were observed in female rats. In the acquisition phase of MWM, aged male rats did not differ significantly from the other two groups in terms of time spent in quadrants, whereas aged female rats spent significantly more time in quadrants compared to the other 2 age groups. Aged male rats also travelled significantly more than the other 2 age groups during the acquisition phase, whereas no such differences were observed in female rats. In both short term (30 min post acquisition) and long term (24 h after acquisition) retrieval phases of MWM, significant gender-related differences were also observed in all age groups. These findings suggest gender- and context-dependent alterations in cognitive functions during aging.
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Affiliation(s)
- Mzia G Zhvania
- School of Natural Sciences and Medicine, Ilia State University, 3/5 K/Cholokashvili Avenue, 0162 Tbilisi, Georgia; Department of Neuron Ultrastructure and Nanoarchitecture, Ivane Beritashvili Center of Experimental Biomedicine, 14 Gotua Street, 9160 Tbilisi, Georgia.
| | - Nadezhda Japaridze
- Department of Neuron Ultrastructure and Nanoarchitecture, Ivane Beritashvili Center of Experimental Biomedicine, 14 Gotua Street, 9160 Tbilisi, Georgia; School of Medicine, New Vision University, 1A Evgeni Mikeladze Street, 0159 Tbilisi, Georgia
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington, DC, USA
| | - Nino Lomidze
- School of Natural Sciences and Medicine, Ilia State University, 3/5 K/Cholokashvili Avenue, 0162 Tbilisi, Georgia
| | - Nino Pochkhidze
- School of Natural Sciences and Medicine, Ilia State University, 3/5 K/Cholokashvili Avenue, 0162 Tbilisi, Georgia; Department of Neuron Ultrastructure and Nanoarchitecture, Ivane Beritashvili Center of Experimental Biomedicine, 14 Gotua Street, 9160 Tbilisi, Georgia
| | - Tamar Lordkipanidze
- School of Natural Sciences and Medicine, Ilia State University, 3/5 K/Cholokashvili Avenue, 0162 Tbilisi, Georgia; Department of Neuron Ultrastructure and Nanoarchitecture, Ivane Beritashvili Center of Experimental Biomedicine, 14 Gotua Street, 9160 Tbilisi, Georgia
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Babaei P, Eyvani K, Kouhestani S. Sex-Independent Cognition Improvement in Response to Kaempferol in the Model of Sporadic Alzheimer's Disease. Neurochem Res 2021; 46:1480-1486. [PMID: 33710535 DOI: 10.1007/s11064-021-03289-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/20/2021] [Accepted: 02/25/2021] [Indexed: 12/11/2022]
Abstract
Alzheimer's disease (AD) is associated with neural oxidative stress and inflammation, and it is assumed to affect more women than men with unknown mechanisms. Kaempferol (KMP) as a potent natural antioxidant has been known to exhibit various biological and pharmacological functions, including antioxidant and anti-inflammatory. We aimed here to evaluate the role of gender difference in response to KMP on the rat model of sporadic AD. Forty-six female and male Wistar rats were divided into six groups of sham, streptozotocin (STZ) + saline (SAL), STZ + KMP. Female rats were ovariectomized, and then all animals received an intracerebroventricular bilateral injection of STZ (3 mg/kg) to induce the AD model. KMP (10 mg/kg) was intraperitoneally administered for 21 consecutive days. Afterward, spatial learning and memory were assessed via the Morris water maze task (MWM). Finally, the hippocampus level of superoxide dismutase (SOD), glutathione, and malondialdehyde were measured using calorimetric kits. Data showed a significant cognition deficit in STZ + SAL compared with the sham. To sum up, we reported that chronic KMP treatment increase significantly improved acquisition and retrieval of spatial memory as evident by longer TTS (total time spent) and short-latency to the platform in MWM. In addition, KMP increased the levels of SOD and glutathione in the hippocampus of rats. Also, KMP decreased hippocampal levels of malondialdehyde in both genders. In conclusion, KMP successfully restores spatial memory impairment independent of gender difference. This memory restoration may at least in part be mediated through boosting the hippocampal level of SOD and glutathione.
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Affiliation(s)
- Parvin Babaei
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Cellular & Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Kimia Eyvani
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Cellular & Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
- Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Somayeh Kouhestani
- Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
- Cellular & Molecular Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
- Department of Physiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
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Martínez-González K, Serrano-Cuevas L, Almeida-Gutiérrez E, Flores-Chavez S, Mejía-Aranguré JM, Garcia-delaTorre P. Citrulline supplementation improves spatial memory in a murine model for Alzheimer's disease. Nutrition 2021; 90:111248. [PMID: 33940559 DOI: 10.1016/j.nut.2021.111248] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/19/2021] [Accepted: 03/18/2021] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Alzheimer's disease (AD) correlates with the dysfunction of metabolic pathways that translates into neurological symptoms. An arginine deficiency, a precursor of nitric oxide (NO), has been reported for patients with AD. We aimed to evaluate the effect of citrulline oral supplementation on cognitive decline in an AD murine model. METHODS Three-month citrulline or water supplementation was blindly given to male and female wild-type and 3 × Tg mice with AD trained and tested in the Morris water maze. Cerebrospinal fluid and brain tissue were collected. Ultra-performance liquid chromatography was used for arginine determinations and the Griess method for NO. RESULTS Eight-month-old male 3 × Tg mice with AD supplemented with citrulline performed significantly better in the Morris water maze task. Arginine levels increased in the cerebrospinal fluid although no changes were seen in brain tissue and only a tendency of increase of NO was observed. CONCLUSIONS Citrulline oral administration is a viable treatment for memory improvement in the early stages of AD, pointing to NO as a viable, efficient target for memory dysfunction in AD.
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Affiliation(s)
- Katia Martínez-González
- Unidad de Investigación Médica en Enfermedades Neurológicas, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México; Posgrado en Ciencias Biológicas, Unidad de Posgrado, Edificio A, 1° Piso, Circuito de Posgrados, Ciudad Universitaria, Coyoacán, C.P. 04510, Distrito Federal, México, Universidad Nacional Autónoma de México
| | - Leonor Serrano-Cuevas
- Coordinación de Unidades Médicas, División de Evaluación y Rendición de Cuentas de los Procesos de Atención Médica en Unidades Médicas de Alta Especialidad, Instituto Mexicano del Seguro Social, México
| | - Eduardo Almeida-Gutiérrez
- Head of Medical Education and Research, Hospital de Cardiología, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México
| | - Salvador Flores-Chavez
- Unidad de Investigación Médica en Nutrición, Hospital de Pediatría, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México
| | | | - Paola Garcia-delaTorre
- Unidad de Investigación Médica en Enfermedades Neurológicas, Hospital de Especialidades, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México.
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9
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Goodman J. Place vs. Response Learning: History, Controversy, and Neurobiology. Front Behav Neurosci 2021; 14:598570. [PMID: 33643005 PMCID: PMC7904695 DOI: 10.3389/fnbeh.2020.598570] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/21/2020] [Indexed: 01/26/2023] Open
Abstract
The present article provides a historical review of the place and response learning plus-maze tasks with a focus on the behavioral and neurobiological findings. The article begins by reviewing the conflict between Edward C. Tolman's cognitive view and Clark L. Hull's stimulus-response (S-R) view of learning and how the place and response learning plus-maze tasks were designed to resolve this debate. Cognitive learning theorists predicted that place learning would be acquired faster than response learning, indicating the dominance of cognitive learning, whereas S-R learning theorists predicted that response learning would be acquired faster, indicating the dominance of S-R learning. Here, the evidence is reviewed demonstrating that either place or response learning may be dominant in a given learning situation and that the relative dominance of place and response learning depends on various parametric factors (i.e., amount of training, visual aspects of the learning environment, emotional arousal, et cetera). Next, the neurobiology underlying place and response learning is reviewed, providing strong evidence for the existence of multiple memory systems in the mammalian brain. Research has indicated that place learning is principally mediated by the hippocampus, whereas response learning is mediated by the dorsolateral striatum. Other brain regions implicated in place and response learning are also discussed in this section, including the dorsomedial striatum, amygdala, and medial prefrontal cortex. An exhaustive review of the neurotransmitter systems underlying place and response learning is subsequently provided, indicating important roles for glutamate, dopamine, acetylcholine, cannabinoids, and estrogen. Closing remarks are made emphasizing the historical importance of the place and response learning tasks in resolving problems in learning theory, as well as for examining the behavioral and neurobiological mechanisms of multiple memory systems. How the place and response learning tasks may be employed in the future for examining extinction, neural circuits of memory, and human psychopathology is also briefly considered.
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Affiliation(s)
- Jarid Goodman
- Department of Psychology, Delaware State University, Dover, DE, United States
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10
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Zorzo C, Arias JL, Méndez M. Retrieval of allocentric spatial memories is preserved up to thirty days and does not require higher brain metabolic demands. Neurobiol Learn Mem 2020; 175:107312. [DOI: 10.1016/j.nlm.2020.107312] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/17/2020] [Accepted: 08/30/2020] [Indexed: 01/13/2023]
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11
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Premachandran H, Zhao M, Arruda-Carvalho M. Sex Differences in the Development of the Rodent Corticolimbic System. Front Neurosci 2020; 14:583477. [PMID: 33100964 PMCID: PMC7554619 DOI: 10.3389/fnins.2020.583477] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
In recent years, a growing body of research has shown sex differences in the prevalence and symptomatology of psychopathologies, such as depression, anxiety, and fear-related disorders, all of which show high incidence rates in early life. This has highlighted the importance of including female subjects in animal studies, as well as delineating sex differences in neural processing across development. Of particular interest is the corticolimbic system, comprising the hippocampus, amygdala, and medial prefrontal cortex. In rodents, these corticolimbic regions undergo dynamic changes in early life, and disruption to their normative development is believed to underlie the age and sex-dependent effects of stress on affective processing. In this review, we consolidate research on sex differences in the hippocampus, amygdala, and medial prefrontal cortex across early development. First, we briefly introduce current principles on sexual differentiation of the rodent brain. We then showcase corticolimbic regional sex differences in volume, morphology, synaptic organization, cell proliferation, microglia, and GABAergic signaling, and explain how these differences are influenced by perinatal and pubertal gonadal hormones. In compiling this research, we outline evidence of what and when sex differences emerge in the developing corticolimbic system, and illustrate how temporal dynamics of its maturational trajectory may differ in male and female rodents. This will help provide insight into potential neural mechanisms underlying sex-specific critical windows for stress susceptibility and behavioral emergence.
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Affiliation(s)
| | - Mudi Zhao
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada
| | - Maithe Arruda-Carvalho
- Department of Psychology, University of Toronto Scarborough, Toronto, ON, Canada.,Department of Cell and Systems Biology, University of Toronto Scarborough, Toronto, ON, Canada
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12
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Aarde SM, Genner RM, Hrncir H, Arnold AP, Jentsch JD. Sex chromosome complement affects multiple aspects of reversal-learning task performance in mice. GENES BRAIN AND BEHAVIOR 2020; 20:e12685. [PMID: 32648356 DOI: 10.1111/gbb.12685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/11/2020] [Accepted: 07/06/2020] [Indexed: 02/06/2023]
Abstract
Determining the mechanisms by which the sex-chromosome complement (SCC) affects learning, attention, and impulsivity has implications for observed sex differences in prevalence, severity, and prognosis of psychiatric/neurodevelopmental disorders and syndromes associated with sex-chromosome aneuploidy. Here, Four Core Genotypes (FCG) mice were evaluated in order to assess the separable and/or interacting effects of gonads (testes vs. ovaries) and their secretions and/or SCC (XX vs. XY) acting via non-gonadal mechanisms on behavior. We tested FCG mice on a reversal-learning task that enables the quantification of aspects of learning, attention and impulsivity. Across testing phases (involving the initial acquisition of a spatial discrimination and subsequent reversal learning), overall error rate was larger in XY compared with XX mice. Although XX and XY groups did not differ in the total number of trials required in order to reach a preset performance criterion, analyses of reversal error types showed more perseverative errors in XY than XX mice, with no difference in regressive errors. Additionally, prepotent-response latencies during the reversal phase were shorter in XY males, as compared with both XX gonadal males and females of either SCC, and failures to sustain the observing response were more frequent in XY mice than XX mice during the acquisition phase. These results indicate that SCC affects the characteristic pattern of response selection during acquisition and reversal performance without affecting the overall learning rate. More broadly, these results show direct effects of the SCC on cognitive processes that are relevant to psychiatric/neurodevelopmental disorders and syndromes associated with sex-chromosome aneuploidies.
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Affiliation(s)
- Shawn M Aarde
- Department of Integrative Biology and Physiology, and Laboratory of Neuroendocrinology of the Brain Research Institute, University of California, Los Angeles, California, USA
| | - Rylee M Genner
- Department of Integrative Biology and Physiology, and Laboratory of Neuroendocrinology of the Brain Research Institute, University of California, Los Angeles, California, USA
| | - Haley Hrncir
- Department of Integrative Biology and Physiology, and Laboratory of Neuroendocrinology of the Brain Research Institute, University of California, Los Angeles, California, USA
| | - Arthur P Arnold
- Department of Integrative Biology and Physiology, and Laboratory of Neuroendocrinology of the Brain Research Institute, University of California, Los Angeles, California, USA
| | - James D Jentsch
- Department of Psychology, Binghamton University, Binghamton, New York, USA
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Abstract
The hippocampus is central to spatial learning and stress responsiveness, both of which differ in form and function in males versus females, yet precisely how the hippocampus contributes to these sex differences is largely unknown. In reproductively mature individuals, sex differences in the steroid hormone milieu undergirds many sex differences in hippocampal-related endpoints. However, there is also evidence for developmental programming of adult hippocampal function, with a central role for androgens as well as their aromatized byproduct, estrogens. These include sex differences in cell genesis, synapse formation, dendritic arborization, and excitatory/inhibitory balance. Enduring effects of steroid hormone modulation occur during two developmental epochs, the first being the classic perinatal critical period of sexual differentiation of the brain and the other being adolescence and the associated hormonal changes of puberty. The cellular mechanisms by which steroid hormones enduringly modify hippocampal form and function are poorly understood, but we here review what is known and highlight where attention should be focused.
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14
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Hillerer KM, Slattery DA, Pletzer B. Neurobiological mechanisms underlying sex-related differences in stress-related disorders: Effects of neuroactive steroids on the hippocampus. Front Neuroendocrinol 2019; 55:100796. [PMID: 31580837 PMCID: PMC7115954 DOI: 10.1016/j.yfrne.2019.100796] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 09/26/2019] [Accepted: 09/27/2019] [Indexed: 12/19/2022]
Abstract
Men and women differ in their vulnerability to a variety of stress-related illnesses, but the underlying neurobiological mechanisms are not well understood. This is likely due to a comparative dearth of neurobiological studies that assess male and female rodents at the same time, while human neuroimaging studies often don't model sex as a variable of interest. These sex differences are often attributed to the actions of sex hormones, i.e. estrogens, progestogens and androgens. In this review, we summarize the results on sex hormone actions in the hippocampus and seek to bridge the gap between animal models and findings in humans. However, while effects of sex hormones on the hippocampus are largely consistent in animals and humans, methodological differences challenge the comparability of animal and human studies on stress effects. We summarise our current understanding of the neurobiological mechanisms that underlie sex-related differences in behavior and discuss implications for stress-related illnesses.
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Affiliation(s)
- Katharina M Hillerer
- Department of Obstetrics and Gynaecology, Salzburger Landeskrankenhaus (SALK), Paracelsus Medical University (PMU), Clinical Research Center Salzburg (CRCS), Salzburg, Austria.
| | - David A Slattery
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital, Goethe University, Frankfurt, Germany
| | - Belinda Pletzer
- Department of Psychology, University of Salzburg, Salzburg, Austria; Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria
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15
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Kolmogorova D, Paré C, Kostuck S, Hudson EC, Lebel N, Houlding E, Gregory JG, Ismail N. Pubertal immune stress transiently alters spatial memory processes in adulthood. Psychoneuroendocrinology 2019; 102:261-272. [PMID: 30594819 DOI: 10.1016/j.psyneuen.2018.12.224] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/20/2018] [Accepted: 12/17/2018] [Indexed: 02/08/2023]
Abstract
Pubertal immune challenge can permanently alter hippocampus-dependent memory processes in a sex-specific manner. Although gonadal hormones can influence various cognitive processes, their role in regulating the cognitive sequelae to pubertal immune challenge has not been thoroughly assessed. We examined whether a pubertal immune challenge could affect hippocampus-dependent memory functions in adulthood and whether these effects are regulated by gonadal steroid hormones. We hypothesized that exposure to an immune challenge during puberty would induce sex-specific deficits in the behavioral and cellular correlates of hippocampus-dependent memory during adulthood. At six weeks of age, during the stress-vulnerable pubertal period, male and female CD-1 mice were injected with either saline or the bacterial endotoxin lipopolysaccharide (LPS). Three weeks later, mice underwent either gonadectomy or sham-surgery. At ten weeks of age (i.e., in adulthood), mice began behavioral testing in an open field, Barnes maze, and Morris water maze. Brain tissue was collected at 17 weeks of age and stained for doublecortin and Ki67 to examine migrating neuronal progenitor cells and cellular proliferation in the neurogenic subgranular zone (SGZ) and the cornus ammonis (CA)1 and CA3 regions of the hippocampus. Pubertal LPS treatment impaired learning during adulthood in both sexes and increased cellular proliferation in the CA1 region in castrated males only. Although adult sex hormones did not reliably modulate these changes, gonadectomy impaired learning during the Morris water maze in both sexes. Learning deficits were more prominent during the Barnes maze, which suggests a stress-dependent expression of LPS-induced cognitive deficits. Neurogenesis in the SGZ and cellular proliferation in the CA3 were not affected by pubertal LPS treatment or gonadectomy. These novel findings emphasize the sensitivity of developing cognitive processes during puberty to immune challenges and suggest a possible mechanism for learning-based difficulties in adulthood.
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Affiliation(s)
- Daria Kolmogorova
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
| | - Catherine Paré
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
| | - Sarah Kostuck
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
| | - Ella Christine Hudson
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; School of Biosciences, Cardiff University, Cardiff, Wales, United Kingdom
| | - Nicholas Lebel
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
| | - Elizabeth Houlding
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada
| | - James Gardner Gregory
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; Center for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
| | - Nafissa Ismail
- NISE Laboratory, School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, Ontario, Canada.
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Grissom EM, Hawley WR, Dohanich GP. Organizational effects of testosterone on learning strategy preference and muscarinic receptor binding in prepubertal rats. Horm Behav 2019; 110:1-9. [PMID: 30772326 DOI: 10.1016/j.yhbeh.2019.02.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 01/22/2019] [Accepted: 02/07/2019] [Indexed: 12/21/2022]
Abstract
Prior to puberty, male rats, but not female rats, prefer a striatum-based stimulus-response learning strategy rather than a hippocampus-based place strategy on a water maze task that can be solved using either strategy. Neurochemically, learning strategy preference has been linked to the ratio of cholinergic muscarinic receptor binding in the hippocampus relative to the striatum, with lower ratios displayed by males compared to females and by stimulus-response learners compared to place learners. Sex differences in a variety of different behaviors are established by the organizational influence of testosterone on brain development. Therefore, the current study investigated the potential organizational effects of neonatal testosterone on learning strategy preference and the hippocampus:striatum ratio of muscarinic receptor binding in prepubertal male and female rats. Similar to vehicle-treated control males, prepubertal females treated with testosterone propionate on the first two days of life preferred a stimulus-response strategy on a dual-solution water maze task. Conversely, vehicle-treated prepubertal females were more likely to use a place strategy. Consistent with previous findings, the hippocampus:striatum ratio of muscarinic receptor binding was lower in rats preferring a stimulus-response strategy compared to those using a place strategy and lower in control males compared to control females. However, the hippocampus:striatum ratio was not reversed by neonatal testosterone treatment of females as predicted. The current study is the first to show that sex differences in how a navigational task is learned prior to puberty is impacted by the presence of testosterone during vulnerable periods in brain development.
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Affiliation(s)
- Elin M Grissom
- Loyola University New Orleans, Department of Psychological Sciences, New Orleans, LA 70118, United States of America; Tulane University, Department of Psychology, New Orleans, LA 70118, United States of America; Tulane University, Program in Neuroscience, New Orleans, LA 70118, United States of America.
| | - Wayne R Hawley
- Edinboro University of Pennsylvania, Psychology Department, Edinboro, PA 16444, United States of America; Tulane University, Department of Psychology, New Orleans, LA 70118, United States of America
| | - Gary P Dohanich
- Tulane University, Department of Psychology, New Orleans, LA 70118, United States of America; Tulane University, Program in Neuroscience, New Orleans, LA 70118, United States of America
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17
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Yagi S, Galea LAM. Sex differences in hippocampal cognition and neurogenesis. Neuropsychopharmacology 2019; 44:200-213. [PMID: 30214058 PMCID: PMC6235970 DOI: 10.1038/s41386-018-0208-4] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 12/27/2022]
Abstract
Sex differences are reported in hippocampal plasticity, cognition, and in a number of disorders that target the integrity of the hippocampus. For example, meta-analyses reveal that males outperform females on hippocampus-dependent tasks in rodents and in humans, furthermore women are more likely to experience greater cognitive decline in Alzheimer's disease and depression, both diseases characterized by hippocampal dysfunction. The hippocampus is a highly plastic structure, important for processing higher order information and is sensitive to the environmental factors such as stress. The structure retains the ability to produce new neurons and this process plays an important role in pattern separation, proactive interference, and cognitive flexibility. Intriguingly, there are prominent sex differences in the level of neurogenesis and the activation of new neurons in response to hippocampus-dependent cognitive tasks in rodents. However, sex differences in spatial performance can be nuanced as animal studies have demonstrated that there are task, and strategy choice dependent sex differences in performance, as well as sex differences in the subregions of the hippocampus influenced by learning. This review discusses sex differences in pattern separation, pattern completion, spatial learning, and links between adult neurogenesis and these cognitive functions of the hippocampus. We emphasize the importance of including both sexes when studying genomic, cellular, and structural mechanisms of the hippocampal function.
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Affiliation(s)
- Shunya Yagi
- 0000 0001 2288 9830grid.17091.3eDepartment of Psychology, Graduate Program in Neuroscience, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z3 Canada
| | - Liisa A. M. Galea
- 0000 0001 2288 9830grid.17091.3eDepartment of Psychology, Graduate Program in Neuroscience, Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z3 Canada
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18
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Rashid H, Ahmed T. Gender dependent contribution of muscarinic receptors in memory retrieval under sub-chronic stress. Neurosci Lett 2018; 681:6-11. [PMID: 29775673 DOI: 10.1016/j.neulet.2018.05.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 05/08/2018] [Accepted: 05/14/2018] [Indexed: 12/17/2022]
Abstract
Stress induces retrograde amnesia in humans and rodents. Muscarinic antagonism under normal physiological conditions causes gender dependent impairment in episodic memory retrieval. We aimed to explore the gender dependent role of muscarinic receptors in memory retrieval under sub-chronic stress condition. Male and female mice were trained for Morris water maze test and contextual fear conditioning, followed by 3 h restraint stress per day for five days. Stress was either given alone or in combination with a daily subcutaneous injection of scopolamine (1 mg/kg) or donepezil (1 mg/kg). Control mice were given saline without any stress. Sub-chronic stress (induced for five days) impaired spatial memory retrieval in males (P < 0.005) but not in females (P > 0.05). Stress induced spatial memory recall deficit in male mice was independent of muscarinic receptor activity (P > 0.05). However, stress induced contextual fear memory recall impairment was reversed by donepezil treatment in male (P < 0.005) and female (P < 0.0001) mice. These findings suggest that differential role of muscarinic activity in retrieving different types of memories under stress depends on gender of subjects.
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Affiliation(s)
- Habiba Rashid
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad, 44000, Pakistan
| | - Touqeer Ahmed
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Sector H-12, Islamabad, 44000, Pakistan.
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Colon L, Odynocki N, Santarelli A, Poulos AM. Sexual differentiation of contextual fear responses. ACTA ACUST UNITED AC 2018; 25:230-240. [PMID: 29661835 PMCID: PMC5903402 DOI: 10.1101/lm.047159.117] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/05/2018] [Indexed: 12/11/2022]
Abstract
Development and sex differentiation impart an organizational influence on the neuroanatomy and behavior of mammalian species. Prior studies suggest that brain regions associated with fear motivated defensive behavior undergo a protracted and sex-dependent development. Outside of adult animals, evidence for developmental sex differences in conditioned fear is sparse. Here, we examined in male and female Long-Evans rats how developmental age and sex affect the long-term retention and generalization of Pavlovian fear responses. Experiments 1 and 2 describe under increasing levels of aversive learning (three and five trials) the long-term retrieval of cued and context fear in preadolescent (P24 and P33), periadolescent (P37), and adult (P60 and P90) rats. Experiments 3 and 4 examined contextual processing under minimal aversive learning (1 trial) procedures in infant (P19, P21), preadolescent (P24), and adult (P60) rats. Here, we found that male and female rats display a divergent developmental trajectory in the expression of context-mediated freezing, such that context fear expression in males tends to increase toward adulthood, while females displayed an opposite pattern of decreasing context fear expression toward adulthood. Longer (14 d) retention intervals produced an overall heightened context fear expression relative to shorter (1 d) retention intervals an observation consistent with fear incubation. Male, but not Female rats showed increasing generalization of context fear across development. Collectively, these findings provide an initial demonstration that sexual differentiation of contextual fear conditioning emerges prior to puberty and follows a distinct developmental trajectory toward adulthood that strikingly parallels sex differences in the etiology and epidemiology of anxiety and trauma- and stressor-related disorders.
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Affiliation(s)
- Lorianna Colon
- Department of Psychology and Center for Neuroscience, University at Albany, State University of New York, Albany, New York, USA
| | - Natalie Odynocki
- Department of Psychology and Center for Neuroscience, University at Albany, State University of New York, Albany, New York, USA
| | - Anthony Santarelli
- Department of Psychology and Center for Neuroscience, University at Albany, State University of New York, Albany, New York, USA
| | - Andrew M Poulos
- Department of Psychology and Center for Neuroscience, University at Albany, State University of New York, Albany, New York, USA
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20
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Tronson NC, Collette KM. (Putative) sex differences in neuroimmune modulation of memory. J Neurosci Res 2017; 95:472-486. [PMID: 27870428 PMCID: PMC5120654 DOI: 10.1002/jnr.23921] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 08/11/2016] [Accepted: 08/22/2016] [Indexed: 12/11/2022]
Abstract
The neuroimmune system is significantly sexually dimorphic, with sex differences evident in the number and activation states of microglia, in the activation of astrocytes, and in cytokine release and function. Neuroimmune cells and signaling are now recognized as critical for many neural functions throughout the life span, including synaptic plasticity and memory function. Here we address the question of how cytokines, astrocytes, and microglia contribute to memory, and specifically how neuroimmune modulation of memory differentially affects males and females. Understanding sex differences in both normal memory processes and dysregulation of memory in psychiatric and neurological disorders is critical for developing treatment and preventive strategies for memory disorders that are effective for both men and women. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Natalie C Tronson
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
| | - Katie M Collette
- Department of Psychology, University of Michigan, Ann Arbor, Michigan
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21
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Koss WA, Frick KM. Sex differences in hippocampal function. J Neurosci Res 2016; 95:539-562. [DOI: 10.1002/jnr.23864] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Revised: 06/28/2016] [Accepted: 07/11/2016] [Indexed: 12/25/2022]
Affiliation(s)
- Wendy A. Koss
- Department of Psychology; University of Wisconsin-Milwaukee; Milwaukee Wisconsin
| | - Karyn M. Frick
- Department of Psychology; University of Wisconsin-Milwaukee; Milwaukee Wisconsin
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22
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Devan BD, Tobin EL, Dunn EN, Magalis C. Sex differences on the competitive place task in the water maze: The influence of peripheral pool time on spatial navigation performance in rats. Behav Processes 2016; 132:34-41. [DOI: 10.1016/j.beproc.2016.09.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 09/03/2016] [Accepted: 09/27/2016] [Indexed: 01/20/2023]
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Yagi S, Chow C, Lieblich SE, Galea LAM. Sex and strategy use matters for pattern separation, adult neurogenesis, and immediate early gene expression in the hippocampus. Hippocampus 2015; 26:87-101. [PMID: 26179150 DOI: 10.1002/hipo.22493] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2015] [Indexed: 12/12/2022]
Abstract
Adult neurogenesis in the dentate gyrus (DG) plays a crucial role for pattern separation, and there are sex differences in the regulation of neurogenesis. Although sex differences, favoring males, in spatial navigation have been reported, it is not known whether there are sex differences in pattern separation. The current study was designed to determine whether there are sex differences in the ability for separating similar or distinct patterns, learning strategy choice, adult neurogenesis, and immediate early gene (IEG) expression in the DG in response to pattern separation training. Male and female Sprague-Dawley rats received a single injection of the DNA synthesis marker, bromodeoxyuridine (BrdU), and were tested for the ability of separating spatial patterns in a spatial pattern separation version of delayed nonmatching to place task using the eight-arm radial arm maze. Twenty-seven days following BrdU injection, rats received a probe trial to determine whether they were idiothetic or spatial strategy users. We found that male spatial strategy users outperformed female spatial strategy users only when separating similar, but not distinct, patterns. Furthermore, male spatial strategy users had greater neurogenesis in response to pattern separation training than all other groups. Interestingly, neurogenesis was positively correlated with performance on similar pattern trials during pattern separation in female spatial strategy users but negatively correlated with performance in male idiothetic strategy users. These results suggest that the survival of new neurons may play an important positive role for pattern separation of similar patterns in females. Furthermore, we found sex and strategy differences in IEG expression in the CA1 and CA3 regions in response to pattern separation. These findings emphasize the importance of studying biological sex on hippocampal function and neural plasticity.
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Affiliation(s)
- Shunya Yagi
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carmen Chow
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephanie E Lieblich
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Liisa A M Galea
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Brain Health, University of British Columbia, Vancouver, British Columbia, Canada
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24
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Duarte-Guterman P, Yagi S, Chow C, Galea LAM. Hippocampal learning, memory, and neurogenesis: Effects of sex and estrogens across the lifespan in adults. Horm Behav 2015; 74:37-52. [PMID: 26122299 DOI: 10.1016/j.yhbeh.2015.05.024] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 04/29/2015] [Accepted: 05/26/2015] [Indexed: 01/12/2023]
Abstract
This article is part of a Special Issue "Estradiol and Cognition". There are sex differences in hippocampus-dependent cognition and neurogenesis suggesting that sex hormones are involved. Estrogens modulate certain forms of spatial and contextual memory and neurogenesis in the adult female rodent, and to a lesser extent male, hippocampus. This review focuses on the effects of sex and estrogens on hippocampal learning, memory, and neurogenesis in the young and aged adult rodent. We discuss how factors such as the type of estrogen, duration and dose of treatment, timing of treatment, and type of memory influence the effects of estrogens on cognition and neurogenesis. We also address how reproductive experience (pregnancy and mothering) and aging interact with estrogens to modulate hippocampal cognition and neurogenesis in females. Given the evidence that adult hippocampal neurogenesis plays a role in long-term spatial memory and pattern separation, we also discuss the functional implications of regulating neurogenesis in the hippocampus.
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Affiliation(s)
- Paula Duarte-Guterman
- Department of Psychology, Centre for Brain Health, Program in Neuroscience, University of British Columbia, Vancouver, Canada
| | - Shunya Yagi
- Department of Psychology, Centre for Brain Health, Program in Neuroscience, University of British Columbia, Vancouver, Canada
| | - Carmen Chow
- Department of Psychology, Centre for Brain Health, Program in Neuroscience, University of British Columbia, Vancouver, Canada
| | - Liisa A M Galea
- Department of Psychology, Centre for Brain Health, Program in Neuroscience, University of British Columbia, Vancouver, Canada.
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25
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Hawley WR, Witty CF, Daniel JM, Dohanich GP. Choline acetyltransferase in the hippocampus is associated with learning strategy preference in adult male rats. Behav Brain Res 2015; 289:118-24. [PMID: 25930215 DOI: 10.1016/j.bbr.2015.04.034] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 03/21/2015] [Accepted: 04/20/2015] [Indexed: 12/24/2022]
Abstract
One principle of the multiple memory systems hypothesis posits that the hippocampus-based and striatum-based memory systems compete for control over learning. Consistent with this notion, previous research indicates that the cholinergic system of the hippocampus plays a role in modulating the preference for a hippocampus-based place learning strategy over a striatum-based stimulus--response learning strategy. Interestingly, in the hippocampus, greater activity and higher protein levels of choline acetyltransferase (ChAT), the enzyme that synthesizes acetylcholine, are associated with better performance on hippocampus-based learning and memory tasks. With this in mind, the primary aim of the current study was to determine if higher levels of ChAT and the high-affinity choline uptake transporter (CHT) in the hippocampus were associated with a preference for a hippocampus-based place learning strategy on a task that also could be solved by relying on a striatum-based stimulus--response learning strategy. Results confirmed that levels of ChAT in the dorsal region of the hippocampus were associated with a preference for a place learning strategy on a water maze task that could also be solved by adopting a stimulus-response learning strategy. Consistent with previous studies, the current results support the hypothesis that the cholinergic system of the hippocampus plays a role in balancing competition between memory systems that modulate learning strategy preference.
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Affiliation(s)
- Wayne R Hawley
- Department of Psychology, Tulane University, New Orleans, LA 70118, USA.
| | - Christine F Witty
- Program in Neuroscience, Tulane University, New Orleans, LA 70118, USA
| | - Jill M Daniel
- Department of Psychology, Tulane University, New Orleans, LA 70118, USA; Program in Neuroscience, Tulane University, New Orleans, LA 70118, USA
| | - Gary P Dohanich
- Department of Psychology, Tulane University, New Orleans, LA 70118, USA; Program in Neuroscience, Tulane University, New Orleans, LA 70118, USA
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26
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Akman O, Moshé SL, Galanopoulou AS. Early life status epilepticus and stress have distinct and sex-specific effects on learning, subsequent seizure outcomes, including anticonvulsant response to phenobarbital. CNS Neurosci Ther 2014; 21:181-92. [PMID: 25311088 DOI: 10.1111/cns.12335] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/14/2014] [Accepted: 09/15/2014] [Indexed: 12/25/2022] Open
Abstract
AIMS Neonatal status epilepticus (SE) is often associated with adverse cognitive and epilepsy outcomes. We investigate the effects of three episodes of kainic acid-induced SE (3KA-SE) and maternal separation in immature rats on subsequent learning, seizure susceptibility, and consequences, and the anticonvulsant effects of phenobarbital, according to sex, type, and age at early life (EL) event. METHODS 3KA-SE or maternal separation was induced on postnatal days (PN) 4-6 or 14-16. Rats were tested on Barnes maze (PN16-19), or lithium-pilocarpine SE (PN19) or flurothyl seizures (PN32). The anticonvulsant effects of phenobarbital (20 or 40 mg/kg/rat, intraperitoneally) pretreatment were tested on flurothyl seizures. FluoroJadeB staining assessed hippocampal injury. RESULTS 3KA-SE or separation on PN4-6 caused more transient learning delays in males and did not alter lithium-pilocarpine SE latencies, but aggravated its outcomes in females. Anticonvulsant effects of phenobarbital were preserved and potentiated in specific groups depending on sex, type, and age at EL event. CONCLUSIONS Early life 3KA-SE and maternal separation cause more but transient cognitive deficits in males but aggravate the consequences of subsequent lithium-pilocarpine SE in females. In contrast, on flurothyl seizures, EL events showed either beneficial or no effect, depending on gender, type, and age at EL events.
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Affiliation(s)
- Ozlem Akman
- Saul R. Korey Department of Neurology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Physiology, Faculty of Medicine, Istanbul Bilim University, Istanbul, Turkey
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27
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Packard MG, Goodman J. Factors that influence the relative use of multiple memory systems. Hippocampus 2014; 23:1044-52. [PMID: 23929809 DOI: 10.1002/hipo.22178] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2013] [Indexed: 01/09/2023]
Abstract
Neurobehavioral evidence supports the existence of at least two anatomically distinct "memory systems" in the mammalian brain that mediate dissociable types of learning and memory; a "cognitive" memory system dependent upon the hippocampus and a "stimulus-response/habit" memory system dependent upon the dorsolateral striatum. Several findings indicate that despite their anatomical and functional distinctiveness, hippocampal- and dorsolateral striatal-dependent memory systems may potentially interact and that, depending on the learning situation, this interaction may be cooperative or competitive. One approach to examining the neural mechanisms underlying these interactions is to consider how various factors influence the relative use of multiple memory systems. The present review examines several such factors, including information compatibility, temporal sequence of training, the visual sensory environment, reinforcement parameters, emotional arousal, and memory modulatory systems. Altering these parameters can lead to selective enhancements of either hippocampal-dependent or dorsolateral striatal-dependent memory, and bias animals toward the use of either cognitive or habit memory in dual-solution tasks that may be solved adequately with either memory system. In many learning situations, the influence of such experimental factors on the relative use of memory systems likely reflects a competitive interaction between the systems. Research examining how various factors influence the relative use of multiple memory systems may be a useful method for investigating how these systems interact with one another.
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Affiliation(s)
- Mark G Packard
- Department of Psychology, Texas A&M University, College Station, Texas
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28
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PKMζ differentially utilized between sexes for remote long-term spatial memory. PLoS One 2013; 8:e81121. [PMID: 24244733 PMCID: PMC3823701 DOI: 10.1371/journal.pone.0081121] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 10/09/2013] [Indexed: 01/08/2023] Open
Abstract
It is well established that male rats have an advantage in acquiring place-learning strategies, allowing them to learn spatial tasks more readily than female rats. However many of these differences have been examined solely during acquisition or in 24h memory retention. Here, we investigated whether sex differences exist in remote long-term memory, lasting 30d after training, and whether there are differences in the expression pattern of molecular markers associated with long-term memory maintenance. Specifically, we analyzed the expression of protein kinase M zeta (PKMζ) and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA2. To adequately evaluate memory retention, we used a robust training protocol to attenuate sex differences in acquisition and found differential effects in memory retention 1d and 30d after training. Female cohorts tested for memory retention 1d after 60 training trials outperformed males by making significantly fewer reference memory errors at test. In contrast, male cohorts tested 30d after 60 training trials outperformed females of the same condition, making fewer reference memory errors and achieving significantly higher retention test scores. Furthermore, given 60 training trials, females tested 30d later showed significantly worse memory compared to females tested 1d later, while males tested 30d later did not differ from males tested 1d later. Together these data suggest that with robust training males do no retain spatial information as well as females do 24h post-training but maintain this spatial information for longer. Males also showed a significant increase in synaptic PKMζ expression and a positive correlation with retention test scores, while females did not. Interestingly, both sexes showed a positive correlation between retention test scores and synaptic GluA2 expression. Furthermore, the increased expression of synaptic PKMζ, associated with male memory but not with female memory, identifies another potential sex-mediated difference in memory processing.
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