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Lu C, Gudowska A, Rutkowska J. What do zebra finches learn besides singing? Systematic mapping of the literature and presentation of an efficient associative learning test. Anim Cogn 2023; 26:1489-1503. [PMID: 37300600 PMCID: PMC10442275 DOI: 10.1007/s10071-023-01795-w] [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: 07/12/2022] [Revised: 04/27/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023]
Abstract
The process of learning in birds has been extensively studied, with a focus on species such as pigeons, parrots, chickens, and crows. In recent years, the zebra finch has emerged as a model species in avian cognition, particularly in song learning. However, other cognitive domains such as spatial memory and associative learning could also be critical to fitness and survival, particularly during the intensive juvenile period. In this systematic review, we provide an overview of cognitive studies on zebra finches, with a focus on domains other than song learning. Our findings indicate that spatial, associative, and social learning are the most frequently studied domains, while motoric learning and inhibitory control have been examined less frequently over 30 years of research. All of the 60 studies included in this review were conducted on captive birds, limiting the generalizability of the findings to wild populations. Moreover, only two of the studies were conducted on juveniles, highlighting the need for more research on this critical period of learning. To address this research gap, we propose a high-throughput method for testing associative learning performance in a large number of both juvenile and adult zebra finches. Our results demonstrate that learning can occur in both age groups, thus encouraging researchers to also perform cognitive tests on juveniles. We also note the heterogeneity of methodologies, protocols, and subject exclusion criteria applied by different researchers, which makes it difficult to compare results across studies. Therefore, we call for better communication among researchers to develop standardised methodologies for studying each cognitive domain at different life stages and also in their natural conditions.
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Affiliation(s)
- ChuChu Lu
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
| | - Agnieszka Gudowska
- Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków, Poland
| | - Joanna Rutkowska
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, Poland
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2
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Day LB, Helmhout W, Pano G, Olsson U, Hoeksema JD, Lindsay WR. Correlated evolution of acrobatic display and both neural and somatic phenotypic traits in manakins (Pipridae). Integr Comp Biol 2021; 61:1343-1362. [PMID: 34143205 DOI: 10.1093/icb/icab139] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/07/2021] [Accepted: 06/15/2021] [Indexed: 12/22/2022] Open
Abstract
Brightly colored manakin (Aves: Pipridae) males are known for performing acrobatic displays punctuated by non-vocal sounds (sonations) in order to attract dull colored females. The complexity of the display sequence and assortment of display elements involved (e.g., sonations, acrobatic maneuvers, and cooperative performances) varies considerably across manakin species. Species-specific display elements coevolve with display-distinct specializations of the neuroanatomical, muscular, endocrine, cardiovascular, and skeletal systems in the handful of species studied. Conducting a broader comparative study, we previously found positive associations between display complexity and both brain mass and body mass across 8 manakin genera, indicating selection for neural and somatic expansion to accommodate display elaboration. Whether this gross morphological variation is due to overall brain and body mass expansion (concerted evolution) versus size increases in only functionally relevant brain regions and growth of particular body ("somatic") features (mosaic evolution) remains to be explored. Here we test the hypothesis that cross-species variation in male brain mass and body mass is driven by mosaic evolution. We predicted positive associations between display complexity and variation in the volume of the cerebellum and sensorimotor arcopallium, brain regions which have roles in sensorimotor processes, and learning and performance of precisely timed and sequenced thoughts and movements, respectively. In contrast, we predicted no associations between the volume of a limbic arcopallial nucleus or a visual thalamic nucleus and display complexity as these regions have no-specific functional relationship to display behavior. For somatic features, we predicted that the relationship between body mass and complexity would not include contributions of tarsus length based on a recent study suggesting selection on tarsus length is less labile than body mass. We tested our hypotheses in males from 12 manakin species and a closely related flycatcher. Our analyses support mosaic evolution of neural and somatic features functionally relevant to display and indicate sexual selection for acrobatic complexity may increase the capacity for procedural learning via cerebellar enlargement and maneuverability via a reduction in tarsus length in species with lower overall complexity scores.
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Affiliation(s)
- Lainy B Day
- Department of Biology, University of Mississippi, 30 University Avenue, University, MS 38677, USA.,Neuroscience Minor, University of Mississippi, 30 University Avenue, University, MS 38677, USA
| | - Wilson Helmhout
- Neuroscience Minor, University of Mississippi, 30 University Avenue, University, MS 38677, USA
| | - Glendin Pano
- Neuroscience Minor, University of Mississippi, 30 University Avenue, University, MS 38677, USA
| | - Urban Olsson
- Department of Biological and Environmental Sciences, University of Gothenburg, Medicinaregatan 18, SE-413-90 Gothenburg, Sweden.,Gothenburg Global Biodiversity Centre, Box 461, SE-405 30 Gothenburg, Sweden
| | - Jason D Hoeksema
- Department of Biology, University of Mississippi, 30 University Avenue, University, MS 38677, USA
| | - Willow R Lindsay
- Department of Biology, University of Mississippi, 30 University Avenue, University, MS 38677, USA.,Department of Biological and Environmental Sciences, University of Gothenburg, Medicinaregatan 18, SE-413-90 Gothenburg, Sweden.,Gothenburg Global Biodiversity Centre, Box 461, SE-405 30 Gothenburg, Sweden
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3
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Goodchild CG, Beck ML, VanDiest I, Czesak FN, Lane SJ, Sewall KB. Male zebra finches exposed to lead (Pb) during development have reduced volume of song nuclei, altered sexual traits, and received less attention from females as adults. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 210:111850. [PMID: 33421715 DOI: 10.1016/j.ecoenv.2020.111850] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/18/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Lead (Pb) is a pervasive global contaminant that interferes with sensitive windows for neurological development and causes oxidative damage to tissues. The effects of moderate and high exposure to Pb have been well-studied in birds, but whether low-level early-life exposure to Pb influences adult phenotype remains unclear. Female songbirds use a male's song and coloration to discriminate between high- and low-quality males. Therefore, if early-life exposure to Pb disrupts song learning ability or shifts the allocation of antioxidant pigments away from colorful secondary sexual traits, male birds exposed to Pb may be less attractive to females. We exposed developing zebra finches (Taeniopygia guttata) to Pb-contaminated drinking water (100 or 1000 parts per billion [ppb]) after hatching (days 0-100). Once male finches reached adulthood (120-150 days post hatch), we measured song learning ability, coloration of bill and cheek patches, and volume of song nuclei in the brain. We also measured female preference for Pb-exposed males relative to control males. Finally, we measured motoric and spatial cognitive performance in male and female finches to assess whether cognitive traits differed in their sensitivity to Pb exposure. Male zebra finches exposed to 1000 ppb Pb had impaired song learning ability, reduced volume of song nuclei, bills with less redness and received less attention from females. Additionally, Pb exposure impaired motoric performance in both male and female finches but did not affect performance in a spatial cognitive task. Adult finches exposed to Pb-contaminated water had higher blood-Pb levels, though in all cases blood-Pb levels were below 7.0 µg dL-1. This study suggests that low-level exposure to Pb contributes to cognitive deficits that persist into adulthood and may indirectly influence fitness by altering secondary sexual traits and reducing male attractiveness.
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Affiliation(s)
- Christopher G Goodchild
- Virgina Tech, Dept. of Biology, Blacksburg, VA, USA; University of Central Oklahoma, Dept. of Biology, Edmond, OK, USA.
| | - Michelle L Beck
- Virgina Tech, Dept. of Biology, Blacksburg, VA, USA; Rivier University, Dept. of Biology, Nashua, NH, USA
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4
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El-Andari R, Cunha F, Tschirren B, Iwaniuk AN. Selection for Divergent Reproductive Investment Affects Neuron Size and Foliation in the Cerebellum. BRAIN, BEHAVIOR AND EVOLUTION 2020; 95:69-77. [PMID: 32784306 DOI: 10.1159/000509068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 06/02/2020] [Indexed: 11/19/2022]
Abstract
The cerebellum has a highly conserved internal circuitry, but varies greatly in size and morphology within and across species. Despite this variation, the underlying volumetric changes among the layers of the cerebellar cortex or their association with Purkinje cell numbers and sizes is poorly understood. Here, we examine intraspecific scaling relationships and variation in the quantitative neuroanatomy of the cerebellum in Japanese quail (Coturnix japonica) selected for high or low reproductive investment. As predicted by the circuitry of the cerebellum, the volumes of the constituent layers of the cerebellar cortex were strongly and positively correlated with one another and with total cerebellar volume. The number of Purkinje cells also significantly and positively co-varied with total cerebellar volume and the molecular layer, but not the granule cell layer or white matter volumes. Purkinje cell size and cerebellar foliation did not significantly covary with any cerebellar measures, but differed significantly between the selection lines. Males and females from the high-investment lines had smaller Purkinje cells than males and females from the low-investment lines and males from the high-investment lines had less folded cerebella than quail from the low-investment lines. These results suggest that within species, the layers of the cerebellum increase in a coordinated fashion, but Purkinje cell size and cerebellar foliation do not increase proportionally with overall cerebellum size. In contrast, selection for differential reproductive investment affects Purkinje cell size and cerebellar foliation, but not other quantitative measures of cerebellar anatomy.
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Affiliation(s)
- Ryaan El-Andari
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Felipe Cunha
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
| | - Barbara Tschirren
- Centre for Ecology and Conservation, University of Exeter, Penryn, United Kingdom
| | - Andrew N Iwaniuk
- Department of Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada,
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5
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Rensel MA, Schlinger BA. The stressed brain: regional and stress-related corticosterone and stress-regulated gene expression in the adult zebra finch (Taeniopygia guttata). J Neuroendocrinol 2020; 32:e12852. [PMID: 32364267 PMCID: PMC7286616 DOI: 10.1111/jne.12852] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 03/16/2020] [Accepted: 04/01/2020] [Indexed: 11/30/2022]
Abstract
Glucocorticoids (CORT) are well-known as important regulators of behaviour and cognition at basal levels and under stress. However, the precise mechanisms governing CORT action and functional outcomes of this action in the brain remain unclear, particularly in model systems other than rodents. In the present study, we investigated the dynamics of CORT regulation in the zebra finch, an important model system for vocal learning, neuroplasticity and cognition. We tested the hypothesis that CORT is locally regulated in the zebra finch brain by quantifying regional and stress-related variation in total CORT across brain regions. In addition, we used an ex vivo slice culture system to test whether CORT regulates target gene expression uniquely in discrete regions of the brain. We documented a robust increase in brain CORT across regions after 30 minutes of restraint stress but, interestingly, baseline and stress-induced CORT levels varied between regions. In addition, CORT treatment of brain slice cultures differentially affected expression of three CORT target genes: it up-regulated expression of FKBP5 in most regions and SGK1 in the hypothalamus only, whereas GILZ was unaffected by CORT treatment across all brain regions investigated. The specific mechanisms producing regional variation in CORT and CORT-dependent downstream gene expression remain unknown, although these data provide additional support for the hypothesis that the songbird brain employs regulatory mechanisms that result in precise control over the influence of CORT on glucocorticoid-sensitive neural circuits.
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Affiliation(s)
- Michelle A. Rensel
- Institute for Society and Genetics, the University of California Los Angeles, Los Angeles, CA
- Laboratory of Neuroendocrinology, the University of California Los Angeles, Los Angeles, CA
- Corresponding author (MAR)
| | - Barney A. Schlinger
- Laboratory of Neuroendocrinology, the University of California Los Angeles, Los Angeles, CA
- Dept. of Integrative Biology and Physiology, the University of California Los Angeles, Los Angeles, CA
- Dept. of Ecology and Evolutionary Biology, the University of California Los Angeles, Los Angeles, CA
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6
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Prabhat A, Jha NA, Taufique SKT, Kumar V. Dissociation of circadian activity and singing behavior from gene expression rhythms in the hypothalamus, song control nuclei and cerebellum in diurnal zebra finches. Chronobiol Int 2019; 36:1268-1284. [DOI: 10.1080/07420528.2019.1637887] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
| | | | | | - Vinod Kumar
- Department of Zoology, University of Delhi, Delhi, India
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7
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Farag A, Lashen S, Eltaysh R. Histoarchitecture restoration of cerebellar sub-layers as a response to estradiol treatment following Kainic acid-induced spinal cord injury. Cell Tissue Res 2019; 376:309-323. [PMID: 30788578 DOI: 10.1007/s00441-019-02992-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 12/29/2018] [Indexed: 12/19/2022]
Abstract
One of the major impacts of spinal cord injury (SCI) is the cerebellar neurological malfunction and deformation of its sub-layers. This could be due to the enormous innervation of the spinocerebellar tract from the posterior gray horn in the spinal cord to the ipsilateral cerebellum. Although the neuroprotective role of estradiol in spinal cord (SC) injuries, as well as its ability to delay secondary cell death changes, is well-known, its effect on cerebellar layers is not fully investigated. In this study, a SCI model was achieved by injection of Kainic acid into SC of adult Male Wistar rats in order to assess the effects of SCI on the cerebellum. The animals were classified into SCI group (animals with SCI), estradiol-treated group (animals with SCI and received estradiol), control groups, and sham control group. The microscopical examination 24 h after induction of SCI revealed that KA induced the most characteristics of neurodegeneration including astrocytic propagation and microglial activation. The estradiol was injected intraperitoneally 20 min after induction of SCI, and the samples were collected at 1, 3, 7, 14, and 30 days. Histologically, the estradiol reduced the inflammatory response, enhanced the recovery of molecular, granular, and Purkinje cell layers, and therefore aided in the restoration of layer organization. These findings were also confirmed by immunohistochemical staining and gene expression profiling.
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Affiliation(s)
- Amany Farag
- Department of Cytology and Histology, Faculty of Veterinary Medicine, Mansoura University, Gomhoria St., P.O. box 35516, Mansoura, Egypt.
| | - S Lashen
- Department of Cytology and Histology, Faculty of Veterinary Medicine, Mansoura University, Gomhoria St., P.O. box 35516, Mansoura, Egypt
| | - R Eltaysh
- Department of Pharmacology, Faculty of Veterinary Medicine, Mansoura University, Gomhoria St., P.O. box 35516, Mansoura, Egypt
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8
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Zsarnovszky A, Kiss D, Jocsak G, Nemeth G, Toth I, Horvath TL. Thyroid hormone- and estrogen receptor interactions with natural ligands and endocrine disruptors in the cerebellum. Front Neuroendocrinol 2018; 48:23-36. [PMID: 28987779 DOI: 10.1016/j.yfrne.2017.10.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 09/06/2017] [Accepted: 10/04/2017] [Indexed: 10/18/2022]
Abstract
Although the effects of phytoestrogens on brain function is widely unknown, they are often regarded as "natural" and thus as harmless. However, the effects of phytoestrogens or environmental pollutants on brain function is underestimated. Estrogen (17beta-estradiol, E2) and thyroid hormones (THs) play pivotal roles in brain development. In the mature brain, these hormones regulate metabolism on cellular and organismal levels. Thus, E2 and THs do not only regulate the energy metabolism of the entire organism, but simultaneously also regulate important homeostatic parameters of neurons and glia in the CNS. It is, therefore, obvious that the mechanisms through which these hormones exert their effects are pleiotropic and include both intra- and intercellular actions. These hormonal mechanisms are versatile, and the experimental investigation of simultaneous hormone-induced mechanisms is technically challenging. In addition, the normal physiological settings of metabolic parameters depend on a plethora of interactions of the steroid hormones. In this review, we discuss conceptual and experimental aspects of the gonadal and thyroid hormones as they relate to in vitro models of the cerebellum.
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Affiliation(s)
- Attila Zsarnovszky
- Department of Animal Physiology and Animal Health, Faculty of Agricultural and Environmental Sciences, Szent István University, Páter Károly u. 1, H-2100 Gödöllő, Hungary; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA.
| | - David Kiss
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Gergely Jocsak
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Gabor Nemeth
- Department of Obstetrics and Gynecology, University of Szeged, School of Medicine, Szeged, Hungary
| | - Istvan Toth
- Departments of Physiology and Biochemistry, University of Veterinary Medicine, Budapest 1078, Hungary
| | - Tamas L Horvath
- Department of Animal Physiology and Animal Health, Faculty of Agricultural and Environmental Sciences, Szent István University, Páter Károly u. 1, H-2100 Gödöllő, Hungary; Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA; Departments of Anatomy and Histology, University of Veterinary Medicine, Budapest 1078, Hungary.
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9
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Tang YP, Wade J. Sex and age differences in brain-derived neurotrophic factor and vimentin in the zebra finch song system: Relationships to newly generated cells. J Comp Neurol 2015; 524:1081-96. [PMID: 26355496 DOI: 10.1002/cne.23893] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/21/2015] [Accepted: 08/26/2015] [Indexed: 12/12/2022]
Abstract
The neural song circuit is enhanced in male compared with female zebra finches due to differential rates of incorporation and survival of cells between the sexes. Two double-label immunohistochemical experiments were conducted to increase the understanding of relationships between newly generated cells (marked with bromodeoxyuridine [BrdU]) and those expressing brain-derived neurotrophic factor (BDNF) and vimentin, a marker for radial glia. The song systems of males and females were investigated at posthatching day 25 during a heightened period of sexual differentiation (following BrdU injections on days 6-10) and in adulthood (following a parallel injection paradigm). In both HVC (proper name) and the robust nucleus of the arcopallium (RA), about half of the BrdU-positive cells expressed BDNF across sexes and ages. Less than 10% of the BDNF-positive cells expressed BrdU, but this percentage was greater in juveniles than adults. Across both brain regions, more BDNF-positive cells were detected in males compared with females. In RA, the number of these cells was also greater in juveniles than adults. In HVC, the average cross-sectional area covered by the vimentin labeling was greater in males than females and in juveniles compared with adults. In RA, more vimentin was detected in juveniles than adults, and within adults it was greater in females. In juveniles only, BrdU-positive cells appeared in contact with vimentin-labeled fibers in HVC, RA, and Area X. Collectively, the results are consistent with roles of BDNF- and vimentin-labeled cells influencing sexually differentiated plasticity of the song circuit.
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Affiliation(s)
- Yu Ping Tang
- Department of Psychology, Michigan State University, East Lansing, Michigan, 48824
| | - Juli Wade
- Neuroscience Program, Michigan State University, East Lansing, Michigan, 48824
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10
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Baumann O, Borra RJ, Bower JM, Cullen KE, Habas C, Ivry RB, Leggio M, Mattingley JB, Molinari M, Moulton EA, Paulin MG, Pavlova MA, Schmahmann JD, Sokolov AA. Consensus paper: the role of the cerebellum in perceptual processes. CEREBELLUM (LONDON, ENGLAND) 2015; 14:197-220. [PMID: 25479821 PMCID: PMC4346664 DOI: 10.1007/s12311-014-0627-7] [Citation(s) in RCA: 287] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Various lines of evidence accumulated over the past 30 years indicate that the cerebellum, long recognized as essential for motor control, also has considerable influence on perceptual processes. In this paper, we bring together experts from psychology and neuroscience, with the aim of providing a succinct but comprehensive overview of key findings related to the involvement of the cerebellum in sensory perception. The contributions cover such topics as anatomical and functional connectivity, evolutionary and comparative perspectives, visual and auditory processing, biological motion perception, nociception, self-motion, timing, predictive processing, and perceptual sequencing. While no single explanation has yet emerged concerning the role of the cerebellum in perceptual processes, this consensus paper summarizes the impressive empirical evidence on this problem and highlights diversities as well as commonalities between existing hypotheses. In addition to work with healthy individuals and patients with cerebellar disorders, it is also apparent that several neurological conditions in which perceptual disturbances occur, including autism and schizophrenia, are associated with cerebellar pathology. A better understanding of the involvement of the cerebellum in perceptual processes will thus likely be important for identifying and treating perceptual deficits that may at present go unnoticed and untreated. This paper provides a useful framework for further debate and empirical investigations into the influence of the cerebellum on sensory perception.
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Affiliation(s)
- Oliver Baumann
- Queensland Brain Institute, The University of Queensland, St. Lucia, Queensland, Australia,
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11
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Schlinger BA, Remage-Healey L, Rensel M. Establishing regional specificity of neuroestrogen action. Gen Comp Endocrinol 2014; 205:235-41. [PMID: 24726987 PMCID: PMC4348095 DOI: 10.1016/j.ygcen.2014.03.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Revised: 03/10/2014] [Accepted: 03/25/2014] [Indexed: 01/03/2023]
Abstract
The specificity of estrogen signaling in brain is defined at one level by the types and distributions of receptor molecules that are activated by estrogens. At another level, as our understanding of the neurobiology of the estrogen synthetic enzyme aromatase has grown, questions have emerged as to how neuroactive estrogens reach specific target receptors in functionally relevant concentrations. Here we explore the spatial specificity of neuroestrogen signaling with a focus on studies of songbirds to provide perspective on some as-yet unresolved questions. Studies conducted in both male and female songbirds have helped to clarify these interesting facets of neuroestrogen physiology.
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Affiliation(s)
- Barney A Schlinger
- Dept. of Integrative Biology and Physiology and the Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, CA, USA.
| | - Luke Remage-Healey
- Neuroscience and Behavior Program, Molecular and Cellular Biology Program, Center for Neuroendocrine Studies, University of Massachusetts, Amherst, MA, USA
| | - Michelle Rensel
- Dept. of Integrative Biology and Physiology and the Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, CA, USA
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12
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Fusani L, Donaldson Z, London SE, Fuxjager MJ, Schlinger BA. Expression of androgen receptor in the brain of a sub-oscine bird with an elaborate courtship display. Neurosci Lett 2014; 578:61-5. [PMID: 24954076 PMCID: PMC4359618 DOI: 10.1016/j.neulet.2014.06.028] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 06/04/2014] [Accepted: 06/11/2014] [Indexed: 01/12/2023]
Abstract
Sex steroids control vertebrate behavior by modulating neural circuits specialized for sex steroid sensitivity. In birds, receptors for androgens (AR) and estrogens (ERα) show conserved expression in neural circuits controlling copulatory and vocal behaviors. Male golden-collared manakins have become a model for evaluating hormonal control of complex physical courtship displays. These birds perform visually and acoustically elaborate displays involving considerable neuromuscular coordination. Androgens activate manakin courtship and AR are expressed widely in spinal circuits and peripheral muscles utilized in courtship. Using in situ hybridization, we report here the distributions of AR and ERα mRNA in the brains of golden-collared manakins. Overall patterns of AR and ERα mRNA expression resemble what has been observed in non-vocal learning species. Notably, however, we detected a large area of AR expression in the arcopallium, a forebrain region that contains a crucial premotor song nucleus in vocal learning species. These results support the idea that AR signaling both centrally and peripherally is responsible for the activation of male manakin courtship, and the arcopallium is likely a premotor site for AR-mediated displays.
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Affiliation(s)
- Leonida Fusani
- Department of Life Science and Biotechnology, University of Ferrara, 44121 Ferrara, Italy.
| | - Zoe Donaldson
- Division of Integrative Neuroscience, Department of Psychiatry, Columbia University, New York, NY 10023, USA
| | - Sarah E London
- Department of Psychology, Institute for Mind and Biology, University of Chicago, Chicago, IL, USA
| | - Matthew J Fuxjager
- Departments of Integrative Biology and Physiology, Ecology and Evolutionary Biology and the Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, CA 90095, USA
| | - Barney A Schlinger
- Departments of Integrative Biology and Physiology, Ecology and Evolutionary Biology and the Laboratory of Neuroendocrinology, Brain Research Institute, University of California, Los Angeles, CA 90095, USA.
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13
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Aromatase, estrogen receptors and brain development in fish and amphibians. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:152-62. [PMID: 25038582 DOI: 10.1016/j.bbagrm.2014.07.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/19/2014] [Accepted: 07/07/2014] [Indexed: 12/20/2022]
Abstract
Estrogens affect brain development of vertebrates, not only by impacting activity and morphology of existing circuits, but also by modulating embryonic and adult neurogenesis. The issue is complex as estrogens can not only originate from peripheral tissues, but also be locally produced within the brain itself due to local aromatization of androgens. In this respect, teleost fishes are quite unique because aromatase is expressed exclusively in radial glial cells, which represent pluripotent cells in the brain of all vertebrates. Expression of aromatase in the brain of fish is also strongly stimulated by estrogens and some androgens. This creates a very intriguing positive auto-regulatory loop leading to dramatic aromatase expression in sexually mature fish with elevated levels of circulating steroids. Looking at the effects of estrogens or anti-estrogens in the brain of adult zebrafish showed that estrogens inhibit rather than stimulate cell proliferation and newborn cell migration. The functional meaning of these observations is still unclear, but these data suggest that the brain of fish is experiencing constant remodeling under the influence of circulating steroids and brain-derived neurosteroids, possibly permitting a diversification of sexual strategies, notably hermaphroditism. Recent data in frogs indicate that aromatase expression is limited to neurons and do not concern radial glial cells. Thus, until now, there is no other example of vertebrates in which radial progenitors express aromatase. This raises the question of when and why these new features were gained and what are their adaptive benefits. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
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14
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Prior NH, Yap KN, Soma KK. Acute and chronic effects of an aromatase inhibitor on pair-maintenance behavior of water-restricted zebra finch pairs. Gen Comp Endocrinol 2014; 196:62-71. [PMID: 24231681 DOI: 10.1016/j.ygcen.2013.10.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 10/06/2013] [Accepted: 10/29/2013] [Indexed: 01/25/2023]
Abstract
Zebra finches are highly social songbirds that maintain life-long monogamous pair-bonds. They rely heavily upon these pair-bonds to survive their ever-changing and unpredictable habitat in the Australian desert. These pair-bonds are maintained via a large repertoire of affiliative behaviors that for most of an individual's life are predominately associated with pair maintenance. Water restriction reduces circulating testosterone levels in male zebra finches and the size of the ovary and oviduct in female zebra finches, but water restriction has little or no effects on pair-maintenance behaviors and local levels of testosterone and estradiol in behaviorally-relevant brain regions. These data suggest that in water-restricted zebra finches, local synthesis of testosterone and estradiol in the brain may support the expression of pair-maintenance behaviors. Here, we directly test whether pair-maintenance behaviors are regulated by estradiol, acting via non-genomic or genomic mechanisms, in water-restricted (i.e., non-breeding) zebra finches. In two experiments, subjects were treated with an aromatase inhibitor (fadrozole) either acutely or chronically, and a variety of pair-maintenance behaviors were quantified. Additionally, we quantified the effect of acute fadrozole treatment on brain and circulating estradiol and testosterone levels. Acute fadrozole administration rapidly decreased estradiol levels in the circulation and brain of males and also rapidly increased testosterone levels in the circulation and brain of both males and females. However, neither the acute nor chronic fadrozole treatment decreased pair-maintenance behaviors. In one case, acute fadrozole treatment promoted affiliation. These data suggest that pair-maintenance behavior in non-breeding zebra finches is not promoted by estradiol acting via either non-genomic or genomic mechanisms.
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Affiliation(s)
- Nora H Prior
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
| | - Kang Nian Yap
- Department of Psychology, University of British Columbia, Vancouver, BC, Canada
| | - Kiran K Soma
- Department of Psychology, University of British Columbia, Vancouver, BC, Canada; Department of Zoology, University of British Columbia, Vancouver, BC, Canada; Graduate Program in Neuroscience, University of British Columbia, Vancouver, BC, Canada; Brain Research Centre, University of British Columbia, Vancouver, BC, Canada
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15
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Krasheninnikova A. Patterned-string tasks: relation between fine motor skills and visual-spatial abilities in parrots. PLoS One 2013; 8:e85499. [PMID: 24376885 PMCID: PMC3871688 DOI: 10.1371/journal.pone.0085499] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 12/04/2013] [Indexed: 11/18/2022] Open
Abstract
String-pulling and patterned-string tasks are often used to analyse perceptual and cognitive abilities in animals. In addition, the paradigm can be used to test the interrelation between visual-spatial and motor performance. Two Australian parrot species, the galah (Eolophus roseicapilla) and the cockatiel (Nymphicus hollandicus), forage on the ground, but only the galah uses its feet to manipulate food. I used a set of string pulling and patterned-string tasks to test whether usage of the feet during foraging is a prerequisite for solving the vertical string pulling problem. Indeed, the two species used techniques that clearly differed in the extent of beak-foot coordination but did not differ in terms of their success in solving the string pulling task. However, when the visual-spatial skills of the subjects were tested, the galahs outperformed the cockatiels. This supports the hypothesis that the fine motor skills needed for advanced beak-foot coordination may be interrelated with certain visual-spatial abilities needed for solving patterned-string tasks. This pattern was also found within each of the two species on the individual level: higher motor abilities positively correlated with performance in patterned-string tasks. This is the first evidence of an interrelation between visual-spatial and motor abilities in non-mammalian animals.
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Bailey DJ, Ma C, Soma KK, Saldanha CJ. Inhibition of hippocampal aromatization impairs spatial memory performance in a male songbird. Endocrinology 2013; 154:4707-14. [PMID: 24105482 PMCID: PMC3836067 DOI: 10.1210/en.2013-1684] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent studies have revealed the presence and regulation of aromatase at the vertebrate synapse, and identified a critical role played by presynaptic estradiol synthesis in the electrophysiological response to auditory and other social cues. However, if and how synaptic aromatization affects behavior remains to be directly tested. We have exploited 3 characteristics of the zebra finch hippocampus (HP) to test the role of synaptocrine estradiol provision on spatial memory function. Although the zebra finch HP contains abundant aromatase transcripts and enzyme activity, immunocytochemical studies reveal widespread pre- and postsynaptic, but sparse to undetectable somal, localization of this enzyme. Further, the superficial location of the avian HP makes possible the more exclusive manipulation of its neurochemical characteristics without perturbation of the neuropil and the resultant induction of astroglial aromatase. Last, as in other vertebrates, the HP is critical for spatial memory performance in this species. Here we report that local inhibition of hippocampal aromatization impairs spatial memory performance in an ecologically valid food-finding task. Local aromatase inhibition also resulted in lower levels of estradiol in the HP, but not in adjacent brain areas, and was achieved without the induction of astroglial aromatase. The observed decrement in acquisition and subsequent memory performance as a consequence of lowered aromatization was similar to that achieved by lesioning this locus. Thus, hippocampal aromatization, much of which is achieved at the synapse in this species, is critical for spatial memory performance.
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Affiliation(s)
- David J Bailey
- Department of Biology, American University, 4400 Massachusetts Avenue Northwest, Washington, DC 20016.
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Schlinger BA, Barske J, Day L, Fusani L, Fuxjager MJ. Hormones and the neuromuscular control of courtship in the golden-collared manakin (Manacus vitellinus). Front Neuroendocrinol 2013; 34:143-56. [PMID: 23624091 PMCID: PMC3995001 DOI: 10.1016/j.yfrne.2013.04.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 04/15/2013] [Accepted: 04/16/2013] [Indexed: 12/16/2022]
Abstract
Many animals engage in spectacular courtship displays, likely recruiting specialized neural, hormonal and muscular systems to facilitate these performances. Male golden-collared manakins (Manacus vitellinus) of Panamanian rainforests perform physically elaborate courtship displays that include novel forms of visual and acoustic signaling. We study the behavioral neuroendocrinology of this male's courtship, combining field behavioral observations with anatomical, biochemical and molecular laboratory-based studies. Seasonally, male courtship is activated by testosterone with little correspondence between testosterone levels and display intensity. Females prefer males whose displays are exceptionally frequent, fast and accurate. The activation of androgen receptors (AR) is crucial for optimal display performance, with AR expressed at elevated levels in several neuromuscular tissues. Apparently, courtship enlists an elaborate androgen-dependent network that includes spinal motoneurons, skeletal muscles and somatosensory systems. This work highlights the value of studying non-traditional species to illuminate physiological adaptations and, hopefully, stimulates future research on other species with complex behaviors.
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Affiliation(s)
- Barney A Schlinger
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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Cross DJ, Marzluff JM, Palmquist I, Minoshima S, Shimizu T, Miyaoka R. Distinct neural circuits underlie assessment of a diversity of natural dangers by American crows. Proc Biol Sci 2013; 280:20131046. [PMID: 23825209 DOI: 10.1098/rspb.2013.1046] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Social animals encountering natural dangers face decisions such as whether to freeze, flee or harass the threat. The American crow, Corvus brachyrhynchos, conspicuously mobs dangers. We used positron emission tomography to test the hypothesis that distinct neuronal substrates underlie the crow's consistent behavioural response to different dangers. We found that crows activated brain regions associated with attention and arousal (nucleus isthmo-opticus/locus coeruleus), and with motor response (arcopallium), as they fixed their gaze on a threat. However, despite this consistent behavioural and neural response, the sight of a person who previously captured the crow, a person holding a dead crow and a taxidermy-mounted hawk activated distinct forebrain regions (amygdala, hippocampus and portion of the caudal nidopallium, respectively). We suggest that aspects of mobbing behaviour are guided by unique neural circuits that respond to differences in mental processing-learning, memory formation and multisensory discrimination-required to appropriately nuance a risky behaviour to specific dangers.
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Affiliation(s)
- Donna J Cross
- Department of Radiology, University of Washington, Seattle, WA, USA
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Duncan KA, Walters BJ, Saldanha CJ. Traumatized and inflamed--but resilient: glial aromatization and the avian brain. Horm Behav 2013; 63:208-15. [PMID: 22414444 PMCID: PMC9366899 DOI: 10.1016/j.yhbeh.2012.02.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 02/26/2012] [Accepted: 02/27/2012] [Indexed: 01/08/2023]
Abstract
Steroids like estrogens have potent effects on the vertebrate brain, and are provided to neural targets from peripheral and central sources. Estradiol synthesized within the vertebrate CNS modulates neural structure and function, including the pathways involved in neuroprotection, and perhaps, neural repair. Specifically, aromatase; the enzyme responsible for the conversion of testosterone to estradiol, is upregulated in the avian and mammalian brain following disruption of the neuropil by multiple forms of perturbation including mechanical injury, ischemia and excitotoxicity. This injury induced aromatase expression is somewhat unique in that it occurs in astroglia rather than neurons, and is stimulated in response to factors associated with brain damage. In this review, we focus on the induction, expression and consequences of glial aromatization in the songbird brain. We begin with a review of the anatomical consequences of glial estrogen provision followed by a discussion of the cellular mechanisms whereby glial aromatization may affect injury-induced neuroplasticity. We then present the current status of our understanding regarding the inductive role of inflammatory processes in the transcription and translation of astrocytic aromatase. We consider the functional aspects of glial aromatization before concluding with unanswered questions and suggestions for future studies. Birds have long informed us about fundamental questions in endocrinology, immunology, and neuroplasticity; and their unique anatomical and physiological characteristics continue to provide an excellent system in which to learn about brain trauma, inflammation, and neuroprotection.
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Affiliation(s)
- Kelli A. Duncan
- Department of Biology, Vassar College, Poughkeepsie, NY 12604, USA
| | - Bradley J. Walters
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Colin J. Saldanha
- Department of Biology, American University, Washington DC, 20016, USA
- Department of Psychology, American University, Washington DC, 20016, USA
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Context-specific effects of estradiol on spatial learning and memory in the zebra finch. Neurobiol Learn Mem 2012; 100:41-7. [PMID: 23257279 DOI: 10.1016/j.nlm.2012.12.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 12/02/2012] [Accepted: 12/06/2012] [Indexed: 11/23/2022]
Abstract
Estradiol is known to impact cognitive function including spatial learning and memory, with studies focused largely on rodent models. Estrogens can be produced peripherally or centrally as neuroestrogens, and the specific role for neuroestrogens in memory processes remains unresolved. Many songbirds possess remarkable spatial memory capabilities and also express the estrogen synthetic enzyme aromatase abundantly in the hippocampus, suggesting that locally-produced estrogens may promote the acquisition or retrieval of spatial memories in these birds. We examined the effect of estradiol on spatial memory in three contexts in the zebra finch: retrieval after discrimination training, retrieval after familiarization but without discrimination training, and memory acquisition, using a combination of estradiol implants and oral dosing with the aromatase inhibitor fadrozole (FAD). Retrieval of spatial memory in both contexts was impaired when estradiol production was blocked. However, spatial memory acquisition was enhanced when estradiol production was inhibited whereas estradiol replacement impaired acquisition. These results provide evidence for a context-specific role of estradiol in songbird spatial memory, results that find accord with some mammalian studies but have not yet been observed in birds.
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Scalise T, Győrffy A, Tóth I, Kiss D, Somogyi V, Goszleth G, Bartha T, Frenyó L, Zsarnovszky A. Ligand-induced changes in Oestrogen and thyroid hormone receptor expression in the developing rat cerebellum: A comparative quantitative PCR and Western blot study. Acta Vet Hung 2012; 60:263-84. [PMID: 22609997 DOI: 10.1556/avet.2012.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Oestrogen (E2) and thyroid hormones (THs) are key regulators of cerebellar development. Recent reports implicate a complex mechanism through which E2 and THs influence the expression levels of each other's receptors (ERs and TRs) to precisely mediate developmental signals and modulate signal strength. We examined the modulating effects of E2 and THs on the expression levels of their receptor mRNAs and proteins in cultured cerebellar cells obtained from 7-day-old rat pups. Cerebellar granule cell cultures were treated with either E2, THs or a combination of these hormones, and resulting receptor expression levels were determined by quantitative PCR and Western blot techniques. The results were compared to non-treated controls and to samples obtained from 14-day-old in situ cerebella. Additionally, we determined the glial effects on the regulation of ER-TR expression levels. The results show that (i) ER and TR expression depends on the combined presence of E2 and THs; (ii) glial cells mediate the hormonal regulation of neuronal ER-TR expression and (iii) loss of tissue integrity results in characteristic changes in ER-TR expression levels. These observations suggest that both E2 and THs, in adequate amounts, are required for the precise orchestration of cerebellar development and that alterations in the ratio of E2/THs may influence signalling mechanisms involved in neurodevelopment. Comparison of data from in vitro and in situ samples revealed a shift in receptor expression levels after loss of tissue integrity, suggesting that such adjusting/regenerative mechanisms may function after cerebellar tissue injury as well.
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Affiliation(s)
- Trudy Scalise
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Andrea Győrffy
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - István Tóth
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Dávid Kiss
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Virág Somogyi
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Gréta Goszleth
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Tibor Bartha
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - László Frenyó
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
| | - Attila Zsarnovszky
- 1 Szent István University Department of Physiology and Biochemistry, Faculty of Veterinary Sciences István u. 2 H-1078 Budapest Hungary
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Choudhury PR, Lahiri S, Rajamma U. Glutamate mediated signaling in the pathophysiology of autism spectrum disorders. Pharmacol Biochem Behav 2012; 100:841-9. [DOI: 10.1016/j.pbb.2011.06.023] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 05/29/2011] [Accepted: 06/19/2011] [Indexed: 02/02/2023]
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The effect of monosodium glutamate on the cerebellar cortex of male albino rats and the protective role of vitamin C (histological and immunohistochemical study). J Mol Histol 2011; 43:179-86. [DOI: 10.1007/s10735-011-9380-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2011] [Accepted: 11/28/2011] [Indexed: 10/15/2022]
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Soderstrom K, Poklis JL, Lichtman AH. Cannabinoid exposure during zebra finch sensorimotor vocal learning persistently alters expression of endocannabinoid signaling elements and acute agonist responsiveness. BMC Neurosci 2011; 12:3. [PMID: 21211022 PMCID: PMC3025904 DOI: 10.1186/1471-2202-12-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 01/06/2011] [Indexed: 11/25/2022] Open
Abstract
Background Previously we have found that cannabinoid treatment of zebra finches during sensorimotor stages of vocal development alters song patterns produced in adulthood. Such persistently altered behavior must be attributable to changes in physiological substrates responsible for song. We are currently working to identify the nature of such physiological changes, and to understand how they contribute to altered vocal learning. One possibility is that developmental agonist exposure results in altered expression of elements of endocannabinoid signaling systems. To test this hypothesis we have studied effects of the potent cannabinoid receptor agonist WIN55212-2 (WIN) on endocannabinoid levels and densities of CB1 immunostaining in zebra finch brain. Results We found that late postnatal WIN treatment caused a long-term global disregulation of both levels of the endocannabinoid, 2-arachidonyl glycerol (2-AG) and densities of CB1 immunostaining across brain regions, while repeated cannabinoid treatment in adults produced few long-term changes in the endogenous cannabinoid system. Conclusions Our findings indicate that the zebra finch endocannabinoid system is particularly sensitive to exogenous agonist exposure during the critical period of song learning and provide insight into susceptible brain areas.
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Affiliation(s)
- Ken Soderstrom
- Department of Pharmacology and Toxicology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA.
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Azcoitia I, Santos-Galindo M, Arevalo MA, Garcia-Segura LM. Role of astroglia in the neuroplastic and neuroprotective actions of estradiol. Eur J Neurosci 2010; 32:1995-2002. [DOI: 10.1111/j.1460-9568.2010.07516.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Mirzatoni A, Spence RD, Naranjo KC, Saldanha CJ, Schlinger BA. Injury-induced regulation of steroidogenic gene expression in the cerebellum. J Neurotrauma 2010; 27:1875-82. [PMID: 20925573 PMCID: PMC2953929 DOI: 10.1089/neu.2010.1330] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Sex steroids assist adult neural tissue in the protection from and repair of damage resulting from neural injury; some steroids may be synthesized in the brain. Songbirds are especially useful models to explore steroidal neuroprotection and repair. First, the full suite of cholesterol transporters and steroidogenic enzymes are expressed in the zebra finch (ZF) brain. Second, estrogens promote recovery of behavioral function after damage to the adult ZF cerebellum. Third, the estrogen synthetic enzyme aromatase is rapidly upregulated in reactive glia following neural injury, including in the ZF cerebellum. We hypothesized that cerebellar injury would locally upregulate steroidogenic factors upstream of aromatase, providing the requisite substrate for neuroestrogen synthesis. We tested this hypothesis by lesioning the cerebellum of adult songbirds using both males and females that peripherally synthesize steroids in different amounts. We then used quantitative PCR to examine expression of mRNAs for the neurosteroidogenic factors TSPO, StAR, SCC, 3β-HSD, CYP17, and aromatase, at 2 and 8 days post-lesion. Compared to sham lesions, cerebellar lesions significantly upregulated mRNA levels of TSPO and aromatase. Sex differences in response to the lesions were detected for TSPO, StAR, and aromatase. All birds responded to experimental conditions by showing time-dependent changes in the expression of TSPO, SCC, and aromatase, suggesting that acute trauma or stress may impact neurosteroidogensis for many days. These data suggest that the cerebellum is an active site of steroid synthesis in the brain, and each steroidogenic factor likely provides neuroprotection and promotes repair.
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Affiliation(s)
- Anahid Mirzatoni
- Department of Physiological Science (Integrative Biology and Physiology), and Laboratory of Neuroendocrinology, University of California–Los Angeles, Los Angeles, California
| | - Rory D. Spence
- Department of Neurology and Laboratory of Neuroendocrinology, Brain Research Institute, University of California–Los Angeles, Los Angeles, California
| | - Kevin C. Naranjo
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
| | - Colin J. Saldanha
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania
| | - Barney A. Schlinger
- Department of Physiological Science (Integrative Biology and Physiology), and Laboratory of Neuroendocrinology, University of California–Los Angeles, Los Angeles, California
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Abstract
PURPOSE OF REVIEW Aromatase inhibitors have been reported to increase height prediction in boys with short stature, and in boys and girls with gonadotropin-independent precocious puberty. The following review discusses data published since 2008 regarding the safety and efficacy of aromatase inhibitors in pediatric patients. RECENT FINDINGS Third-generation aromatase inhibitors in combination with antiandrogens appear effective in preventing bone age advancement and virilization in boys with familial male-limited precocious puberty (FMPP). Letrozole, but not anastrozole, decreased bleeding episodes and bone age advancement in girls with McCune-Albright syndrome (MAS), despite ovarian enlargement. Letrozole-treated boys with idiopathic short stature (ISS) had no loss of bone density but were noted to have more vertebral abnormalities than a placebo group. Two years of letrozole therapy did not increase predicted adult height in pre and peripubertal boys with ISS when re-assessed 4 years after the treatment period. SUMMARY Aromatase inhibitors together with an antiandrogen appear to be a very promising treatment for FMPP. Further longer-term studies with letrozole are needed in MAS. The prevalence of vertebral deformities should be evaluated prospectively in patients treated with aromatase inhibitors. Adult height data are still lacking in pediatric patients treated with aromatase inhibitors. Two years of therapy in pre and peripubertal short boys does not appear to increase adult height. Hemogram, lipids, and bone density should be periodically assessed in treated patients. Further controlled studies are needed to demonstrate safety and efficacy of aromatase inhibitors in pediatric patients.
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