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Narducci R, Baroncelli L, Sansevero G, Begenisic T, Prontera C, Sale A, Cenni MC, Berardi N, Maffei L. Early impoverished environment delays the maturation of cerebral cortex. Sci Rep 2018; 8:1187. [PMID: 29352131 PMCID: PMC5775315 DOI: 10.1038/s41598-018-19459-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 12/27/2017] [Indexed: 12/26/2022] Open
Abstract
The influence of exposure to impoverished environments on brain development is unexplored since most studies investigated how environmental impoverishment affects adult brain. To shed light on the impact of early impoverishment on developmental trajectories of the nervous system, we developed a protocol of environmental impoverishment in which dams and pups lived from birth in a condition of reduced sensory-motor stimulation. Focusing on visual system, we measured two indexes of functional development, that is visual acuity, assessed by using Visual Evoked Potentials (VEPs), and VEP latency. In addition, we assessed in the visual cortex levels of Insulin-Like Growth Factor 1 (IGF-1) and myelin maturation, together with the expression of the GABA biosynthetic enzyme GAD67. We found that early impoverishment strongly delays visual acuity and VEP latency development. These functional changes were accompanied by a significant reduction of IGF-1 protein and GAD67 expression, as well as by delayed myelination of nerve fibers, in the visual cortex of impoverished pups. Thus, exposure to impoverished living conditions causes a significant alteration of developmental trajectories leading to a prominent delay of brain maturation. These results underscore the significance of adequate levels of environmental stimulation for the maturation of central nervous system.
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Affiliation(s)
- Roberta Narducci
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy.,Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, Area San Salvi - Pad. 26, I-50135, Florence, Italy
| | - Laura Baroncelli
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy.
| | - Gabriele Sansevero
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy.,Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, Area San Salvi - Pad. 26, I-50135, Florence, Italy
| | - Tatjana Begenisic
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy
| | - Concetta Prontera
- Fondazione G. Monasterio CNR-Regione Toscana, via Moruzzi 1, I-56124, Pisa, Italy
| | - Alessandro Sale
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy
| | - Maria Cristina Cenni
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy
| | - Nicoletta Berardi
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy.,Department of Neuroscience, Psychology, Drug Research and Child Health NEUROFARBA, University of Florence, Area San Salvi - Pad. 26, I-50135, Florence, Italy
| | - Lamberto Maffei
- Institute of Neuroscience, National Research Council (CNR), Via Moruzzi 1, I-56124, Pisa, Italy
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Diniz DG, de Oliveira MA, de Lima CM, Fôro CAR, Sosthenes MCK, Bento-Torres J, da Costa Vasconcelos PF, Anthony DC, Diniz CWP. Age, environment, object recognition and morphological diversity of GFAP-immunolabeled astrocytes. Behav Brain Funct 2016; 12:28. [PMID: 27719674 PMCID: PMC5056502 DOI: 10.1186/s12993-016-0111-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/22/2016] [Indexed: 12/12/2022] Open
Abstract
Background Few studies have explored the glial response to a standard environment and how the response may be associated with age-related cognitive decline in learning and memory. Here we investigated aging and environmental influences on hippocampal-dependent tasks and on the morphology of an unbiased selected population of astrocytes from the molecular layer of dentate gyrus, which is the main target of perforant pathway. Results Six and twenty-month-old female, albino Swiss mice were housed, from weaning, in a standard or enriched environment, including running wheels for exercise and tested for object recognition and contextual memories. Young adult and aged subjects, independent of environment, were able to distinguish familiar from novel objects. All experimental groups, except aged mice from standard environment, distinguish stationary from displaced objects. Young adult but not aged mice, independent of environment, were able to distinguish older from recent objects. Only young mice from an enriched environment were able to distinguish novel from familiar contexts. Unbiased selected astrocytes from the molecular layer of the dentate gyrus were reconstructed in three-dimensions and classified using hierarchical cluster analysis of bimodal or multimodal morphological features. We found two morphological phenotypes of astrocytes and we designated type I the astrocytes that exhibited significantly higher values of morphological complexity as compared with type II. Complexity = [Sum of the terminal orders + Number of terminals] × [Total branch length/Number of primary branches]. On average, type I morphological complexity seems to be much more sensitive to age and environmental influences than that of type II. Indeed, aging and environmental impoverishment interact and reduce the morphological complexity of type I astrocytes at a point that they could not be distinguished anymore from type II. Conclusions We suggest these two types of astrocytes may have different physiological roles and that the detrimental effects of aging on memory in mice from a standard environment may be associated with a reduction of astrocytes morphological diversity. Electronic supplementary material The online version of this article (doi:10.1186/s12993-016-0111-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel Guerreiro Diniz
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil.,Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford, England, UK
| | - Marcus Augusto de Oliveira
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil
| | - Camila Mendes de Lima
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil
| | - César Augusto Raiol Fôro
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil
| | - Marcia Consentino Kronka Sosthenes
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil
| | - João Bento-Torres
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil
| | | | - Daniel Clive Anthony
- Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford, England, UK
| | - Cristovam Wanderley Picanço Diniz
- Laboratório de Investigações Em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Universidade Federal do Pará, Hospital Universitário João de Barros Barreto, Rua dos Mundurucus 4487, Guamá, Belém, Pará, CEP 66073-000, Brazil. .,Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford, England, UK.
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Buschler A, Manahan-Vaughan D. Metabotropic glutamate receptor, mGlu5, mediates enhancements of hippocampal long-term potentiation after environmental enrichment in young and old mice. Neuropharmacology 2016; 115:42-50. [PMID: 27267685 DOI: 10.1016/j.neuropharm.2016.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 12/24/2022]
Abstract
The metabotropic glutamate (mGlu) receptor, mGlu5, is of particular relevance for hippocampal function. It is critically required for the expression of long-term potentiation (LTP) and long-term depression (LTD), regulates neuronal oscillations, maintains the stability of place fields and is required for hippocampus-dependent memory. MGlu5-dysfunctions are associated with profound cognitive deficits in humans, and mGlu5 has been targeted as a putative cognitive enhancer. Cognitive enhancement, by means of environmental enrichment (EE) in rodents, results in improved hippocampal synaptic plasticity and memory. Here, we explored whether mGlu5 contributes to these enhancements. MGlu5-antagonism dose-dependently impaired the early phase of LTP (>4 h) in the CA1 region of young(3-4 month old) mice. Late-LTP (>24 h) was also impaired. LTP (>24 h) elicited in old (10-14 month old) mice displayed reduced sensitivity to mGlu5 antagonism. Short-term potentiation (STP, < 2 h) that was elicited by weaker afferent stimulation was unaffected by mGlu5-antagonism in both age-groups. EE significantly amplified STP (<2 h) in old and young animals, but did not increase the duration of synaptic potentiation, or promote induction of LTP. The improvement in STP was prevented by mGlu5-antagonism, in both young and old animals. These results indicate that modifications of the synapse that underlie improvements of LTP by EE require the contribution of mGlu5. Strikingly, although LTP in old mice does not critically depend on mGlu5, improvements in synaptic potentiation resulting from EE are mGlu5-dependent in old mice. Regarded in light of the known role for mGlu5 in hippocampal function and pathophysiology, these data suggest that mGlu5 regulation of synaptic information storage is pivotal to optimal hippocampal function. This article is part of the Special Issue entitled 'Metabotropic Glutamate Receptors, 5 years on'.
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Affiliation(s)
- Arne Buschler
- Ruhr University Bochum, Medical Faculty, Department of Neurophysiology, Bochum, Germany
| | - Denise Manahan-Vaughan
- Ruhr University Bochum, Medical Faculty, Department of Neurophysiology, Bochum, Germany.
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Schaefers ATU. Rearing conditions and domestication background determine regulation of hippocampal cell proliferation and survival in adulthood-laboratory CD1 and C57Bl/6 mice versus wild house mice. Neuroscience 2012; 228:120-7. [PMID: 23079634 DOI: 10.1016/j.neuroscience.2012.10.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Revised: 10/04/2012] [Accepted: 10/05/2012] [Indexed: 11/19/2022]
Abstract
Brain development is sensitive to an individual's interaction with its environment. Deprivation of natural environmental stimulation especially in the phase after weaning has long-lasting consequences on neuroplasticity. However, previous findings concerning the effects of rearing environment on adult hippocampal cell proliferation and neurogenesis in rodents remain contradictory. To address the question, whether the variability of hippocampal plasticity in response to environmental conditions is a unique feature at least in mice, the present study examined the effects of social and physical deprivation during brain development on hippocampal cell production and survival in adults of three mouse strains (Mus musculus) with different domestication background: outbred CD1, inbred C57Bl/6 and the F2-descendants of wild-caught house mice. Wheel running increased cell proliferation rates in the dentate gyrus of CD1 and C57Bl/6 mice reared under socially and physically deprived conditions, but not from enriched conditions. In wild house mice, neither the rearing conditions nor the wheel-running challenge did affect proliferative activity. This indicates, on the one hand, that wild house mice are more robust in their regulation of hippocampal cell proliferation against environmental influences and, on the other hand, that domestication and rearing background of laboratory animals impact neuroplastic potentials and responsiveness to external stimuli in adulthood.
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Affiliation(s)
- A T U Schaefers
- Department of Biology, Bielefeld University, Bielefeld, Germany.
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Abstract
Animals living in an impoverished environment, i.e., without the possibility of physical and social activity, perform worse on cognitive tests compared to animals in an enriched environment. The same cognitive difference is also observed in humans. However, it is not clear whether this difference is caused by a decrease in cognition due to an impoverished environment or an increase due to an enriched environment. This review discusses the impact of an impoverished environment on cognition in animal experimental studies and human experimental studies with community-dwelling and institutionalized older people. Results show that the cognitive functioning of old rats is more affected by an impoverished environment than young rats. Similarly, sedentary and lonely people (impoverished environment) have worse cognitive functioning and show a faster cognitive decline than physically and socially active people. Institutionalization further aggravates cognitive decline, probably due to the impoverished environment of nursing homes. In institutions, residents spend an unnecessary and excessive amount of time in bed; out of bed they show mainly sedentary or completely passive behavior. In conclusion, older people, especially those that have been institutionalized, have poor levels of physical and social activity, which in turn has a negative impact on cognitive functioning.
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Affiliation(s)
- Karin M Volkers
- Department of Clinical Neuropsychology, Faculty of Psychology and Education, VU University, 1081 BT Amsterdam, The Netherlands.
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