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Saxena R, McNaughton BL. Bridging Neuroscience and AI: Environmental Enrichment as a Model for Forward Knowledge Transfer. ARXIV 2024:arXiv:2405.07295v2. [PMID: 38947919 PMCID: PMC11213130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Continual learning (CL) refers to an agent's capability to learn from a continuous stream of data and transfer knowledge without forgetting old information. One crucial aspect of CL is forward transfer, i.e., improved and faster learning on a new task by leveraging information from prior knowledge. While this ability comes naturally to biological brains, it poses a significant challenge for artificial intelligence (AI). Here, we suggest that environmental enrichment (EE) can be used as a biological model for studying forward transfer, inspiring human-like AI development. EE refers to animal studies that enhance cognitive, social, motor, and sensory stimulation and is a model for what, in humans, is referred to as 'cognitive reserve'. Enriched animals show significant improvement in learning speed and performance on new tasks, typically exhibiting forward transfer. We explore anatomical, molecular, and neuronal changes post-EE and discuss how artificial neural networks (ANNs) can be used to predict neural computation changes after enriched experiences. Finally, we provide a synergistic way of combining neuroscience and AI research that paves the path toward developing AI capable of rapid and efficient new task learning.
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Affiliation(s)
- Rajat Saxena
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
| | - Bruce L McNaughton
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA 92697, USA
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, T1K 3M4 Canada
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2
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Khalil MH. Environmental enrichment: a systematic review on the effect of a changing spatial complexity on hippocampal neurogenesis and plasticity in rodents, with considerations for translation to urban and built environments for humans. Front Neurosci 2024; 18:1368411. [PMID: 38919908 PMCID: PMC11196820 DOI: 10.3389/fnins.2024.1368411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 05/21/2024] [Indexed: 06/27/2024] Open
Abstract
Introduction Hippocampal neurogenesis is critical for improving learning, memory, and spatial navigation. Inhabiting and navigating spatial complexity is key to stimulating adult hippocampal neurogenesis (AHN) in rodents because they share similar hippocampal neuroplasticity characteristics with humans. AHN in humans has recently been found to persist until the tenth decade of life, but it declines with aging and is influenced by environmental enrichment. This systematic review investigated the impact of spatial complexity on neurogenesis and hippocampal plasticity in rodents, and discussed the translatability of these findings to human interventions. Methods Comprehensive searches were conducted on three databases in English: PubMed, Web of Science, and Scopus. All literature published until December 2023 was screened and assessed for eligibility. A total of 32 studies with original data were included, and the process is reported in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and checklist. Results The studies evaluated various models of spatial complexity in rodents, including environmental enrichment, changes to in-cage elements, complex layouts, and navigational mazes featuring novelty and intermittent complexity. A regression equation was formulated to synthesize key factors influencing neurogenesis, such as duration, physical activity, frequency of changes, diversity of complexity, age, living space size, and temperature. Conclusion Findings underscore the cognitive benefits of spatial complexity interventions and inform future translational research from rodents to humans. Home-cage enrichment and models like the Hamlet complex maze and the Marlau cage offer insight into how architectural design and urban navigational complexity can impact neurogenesis in humans. In-space changing complexity, with and without physical activity, is effective for stimulating neurogenesis. While evidence on intermittent spatial complexity in humans is limited, data from the COVID-19 pandemic lockdowns provide preliminary evidence. Existing equations relating rodent and human ages may allow for the translation of enrichment protocol durations from rodents to humans.
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Lewis A. A non-adaptationist hypothesis of play behaviour. J Physiol 2024; 602:2433-2453. [PMID: 37656171 DOI: 10.1113/jp284413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 08/16/2023] [Indexed: 09/02/2023] Open
Abstract
Play is a suite of apparently non-functional, pleasurable behaviours observed in human and non-human animals. Although the phenomenon has been studied extensively, no adaptationist behavioural theory of how play evolved can be supported by the available evidence. However, the advancement of the extended evolutionary synthesis and developments in systems biology offer alternative avenues for non-adaptationist physiological hypotheses. I therefore propose a hypothesis of play, based upon a complex ACh activity that is under agential control of the organism, whereby play initiates ACh-mediated feedforward and feedback processes which act to: (i) regulate metabolic processes; (ii) form new ACh receptors via ACh mRNA activity; (iii) mediate attention, memory consolidation and learning; and (iv) mediate social behaviours, reproduction and embryonic development. However, play occurs across taxa, but does not occur across all taxonomic groups or within all species of a taxonomic group. Thus, to support the validity of the proposed hypothesis, I further propose potential explanations for this anomaly, which include sampling and observer biases, altricial versus precocial juvenile development, and the influence of habitat niche and environmental conditions on behaviour. The proposed hypothesis thus offers new avenues for study in both the biological and social sciences, in addition to having potential applications in applied sciences, such as animal welfare and biomedical research. Crucially, it is hoped that this hypothesis will promote further study of a valid and behaviourally significant, yet currently enigmatic, biological phenomenon.
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Affiliation(s)
- Amelia Lewis
- Independent Researcher, Lincoln, Lincolnshire, UK
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Barrientos-Bonilla AA, Pensado-Guevara PB, Puga-Olguín A, Nadella R, Sánchez-García ADC, Zavala-Flores LM, Villanueva-Olivo A, Cibrián-Llanderal IT, Rovirosa-Hernández MDJ, Hernandez-Baltazar D. BrdU does not induce hepatocellular damage in experimental Wistar rats. Acta Histochem 2024; 126:152117. [PMID: 38016413 DOI: 10.1016/j.acthis.2023.152117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 11/03/2023] [Accepted: 11/13/2023] [Indexed: 11/30/2023]
Abstract
Bromodeoxyuridine (BrdU) is used in studies related to cell proliferation and neurogenesis. The multiple intraperitoneal injections of this molecule could favor liver function profile changes. In this study, we evaluate the systemic and hepatocellular impact of BrdU in male adult Wistar rats in 30 %-partial hepatectomy (PHx) model. The rats received BrdU 50 mg/Kg by intraperitoneal injection at 0.5, 1, 2, 3, 6, 9 and 16 days after 30 %-PH. The rats were distributed into four groups as follows, control, sham, PHx/BrdU(-) and PHx/BrdU(+). On day 16, we evaluated hepatocellular nuclei and analyzed histopathological features by haematoxylin-eosin stain and apoptotic profile was qualified by caspase-3 presence. The systemic effect was evaluated by liver markers such as alanine transferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (AP), bilirubin, total proteins and serum albumin content. The statistical analysis consisted of a student t-test and one-way ANOVA. BrdU did not induce apoptosis or hepatocellular damage in male rats. Multiple administrations of BrdU in male rats did not induce significant decrease body weight, but increased serum ALT and LDH levels were found. Our results show that the BrdU does not produce hepatocellular damage.
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Affiliation(s)
| | | | - Abraham Puga-Olguín
- Unidad de Salud Integrativa, Centro de EcoAlfabetización y Diálogo de Saberes, Universidad Veracruzana, Xalapa, Veracruz, Mexico
| | | | | | | | - Arnulfo Villanueva-Olivo
- Departamento de Histología. Facultad de Medicina. Universidad Autónoma de Nuevo León, Monterrey, Nuevo León, Mexico
| | | | | | - Daniel Hernandez-Baltazar
- Instituto de Neuroetología, Universidad Veracruzana, Xalapa, Veracruz, Mexico; Investigadoras e investigadores por México CONAHCyT-Instituto de Neuroetología, Universidad Veracruzana, Mexico.
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Duarte-Guterman P, Richard JE, Lieblich SE, Eid RS, Lamers Y, Galea LAM. Cellular and molecular signatures of motherhood in the adult and ageing rat brain. Open Biol 2023; 13:230217. [PMID: 37989220 PMCID: PMC10681025 DOI: 10.1098/rsob.230217] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 10/23/2023] [Indexed: 11/23/2023] Open
Abstract
Pregnancy is marked by robust changes, including brain changes to volume, structure, connectivity and neuroplasticity. Although some brain changes are restricted to pregnancy and the postpartum, others are long-lasting. Few studies have examined possible mechanisms of these changes or the effects of multiple pregnancies. We characterized various cellular and molecular signatures of parity (nulliparous, primiparous, biparous) in the rat hippocampus. We investigated density of neural stems cells (Sox2), microglia (Iba-1) and levels of a synaptic protein (PSD-95), cell signalling pathways, neuroinflammation, and the tryptophan-kynurenine (TRP-KYN) pathway, one week after weaning their pups from the last pregnancy (age of dam: seven months) and in middle-age (age of dam: 13 months). Parity increased PSD-95 levels in both age groups and prevented the age-related decrease in neural stem cell density observed in nulliparous rats. Biparity increased cell signalling phosphoproteins (pp70S6K, S6RP) and number of microglia in the dentate gyrus, regardless of age. Parity resulted in transient changes to the TRP-KYN system. Thus, previous parity has lasting effects on synaptic plasticity with fewer lasting effects on inflammation and cell signalling phosphoproteins in the whole hippocampus.
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Affiliation(s)
- P. Duarte-Guterman
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
| | - J. E. Richard
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - S. E. Lieblich
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
| | - R. S. Eid
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Y. Lamers
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
- Institute for Neuroscience and Physiology, University of Gothenburg, Sweden
| | - L. A. M. Galea
- Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada
- Graduate Program in Neuroscience, University of British Columbia, Vancouver, British Columbia, Canada
- Djavad Mowafaghian Centre for Brain health, University of British Columbia, Vancouver, British Columbia, Canada
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Stepanichev M, Aniol V, Lazareva N, Gulyaeva N. Decreased Hippocampal Neurogenesis in Aged Male Wistar Rats Is Not Associated with Memory Acquisition in a Water Maze. Int J Mol Sci 2023; 24:13276. [PMID: 37686083 PMCID: PMC10487931 DOI: 10.3390/ijms241713276] [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: 07/31/2023] [Revised: 08/12/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023] Open
Abstract
Brain aging is associated with a progressive decrease in learning abilities, memory, attention, decision making, and sensory perception. Age-related cognitive disturbances may be related to a decrease in the functional capacities of the hippocampus. This brain region is essential for learning and memory, and the lifelong neurogenesis occurring in the subgranular zone of the dentate gyrus may be a key event mediating the mnemonic functions of the hippocampus. In the present study, we investigated whether age-related changes in hippocampal neurogenesis are associated with learning and memory disturbances. Four- and 24-month-old rats were trained to find a hidden platform in a water maze. Though the older group showed higher latency to search the platform as compared to the younger group, both groups learned the task. However, the density of proliferating (PCNA-positive), differentiating (Dcx-positive), and new neurons (pre-labeled BrdU-positive) was significantly lower in the hippocampus of aged rats as compared to young ones. This inhibition of neurogenesis could be related to increased local production of nitric oxide since the density of neurons expressing neuronal NO-synthase was higher in the aged hippocampus. Thus, we can suggest that an age-related decrease in neurogenesis is not directly associated with place learning in aged rats.
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Affiliation(s)
- Mikhail Stepanichev
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Butlerova Str., 5a, Moscow 117485, Russia; (V.A.); (N.L.); (N.G.)
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Carvajal F, Sánchez-Gil A, Cardona D, Rincón-Cervera MA, Lerma-Cabrera JM. The Effect of Very-Long-Chain n-3 Polyunsaturated Fatty Acids in the Central Nervous System and Their Potential Benefits for Treating Alcohol Use Disorder: Reviewing Pre-Clinical and Clinical Data. Nutrients 2023; 15:2993. [PMID: 37447319 DOI: 10.3390/nu15132993] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 06/28/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
Alcohol use poses a significant global health concern, leading to serious physical and socioeconomic issues worldwide. The current treatment options for problematic alcohol consumption are limited, leading to the exploration of alternative approaches, such as nutraceuticals. One promising target is very-long-chain n-3 polyunsaturated fatty acids (VLC n-3 PUFAs). This review aims to compile the most relevant pre-clinical and clinical evidence on the effect of VLC n-3 PUFAs on alcohol use disorders and related outcomes. The findings suggest that VLC n-3 PUFAs may alleviate the physiological changes induced by alcohol consumption, including neuroinflammation and neurotransmitter dysregulation. Additionally, they can reduce withdrawal symptoms, improve mood, and reduce stress level, all of which are closely associated with problematic alcohol consumption. However, more research is required to fully understand the precise mechanisms by which VLC n-3 PUFAs exert their function. Furthermore, PUFAs should not be considered a standalone solution, but as a complement to other therapeutic approaches. Although preliminary evidence supports the potential therapeutic effect of VLC n-3 PUFAs on problematic alcohol consumption, additional research is needed to validate these findings and determine the optimal use of PUFAs as part of a comprehensive approach to the treatment of alcohol use disorders.
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Affiliation(s)
- Francisca Carvajal
- Department of Psychology, University of Almeria, 04120 Almeria, Spain
- Health Research Center, University of Almeria, 04120 Almeria, Spain
| | - Ainhoa Sánchez-Gil
- Department of Psychology, University of Almeria, 04120 Almeria, Spain
- Health Research Center, University of Almeria, 04120 Almeria, Spain
| | - Diana Cardona
- Health Research Center, University of Almeria, 04120 Almeria, Spain
- Department of Nursing, Physiotherapy and Medicine, University of Almeria, 04120 Almeria, Spain
| | - Miguel Angel Rincón-Cervera
- Food Technology Division, ceiA3, CIAMBITAL, University of Almeria, 04120 Almeria, Spain
- Institute of Nutrition and Food Technology, University of Chile, Santiago 830490, Chile
| | - Jose Manuel Lerma-Cabrera
- Department of Psychology, University of Almeria, 04120 Almeria, Spain
- Health Research Center, University of Almeria, 04120 Almeria, Spain
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8
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Rubinstein MR, Burgueño AL, Quiroga S, Wald MR, Genaro AM. Current Understanding of the Roles of Gut-Brain Axis in the Cognitive Deficits Caused by Perinatal Stress Exposure. Cells 2023; 12:1735. [PMID: 37443769 PMCID: PMC10340286 DOI: 10.3390/cells12131735] [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: 04/17/2023] [Revised: 06/15/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023] Open
Abstract
The term 'perinatal environment' refers to the period surrounding birth, which plays a crucial role in brain development. It has been suggested that dynamic communication between the neuro-immune system and gut microbiota is essential in maintaining adequate brain function. This interaction depends on the mother's status during pregnancy and/or the newborn environment. Here, we show experimental and clinical evidence that indicates that the perinatal period is a critical window in which stress-induced immune activation and altered microbiota compositions produce lasting behavioral consequences, although a clear causative relationship has not yet been established. In addition, we discuss potential early treatments for preventing the deleterious effect of perinatal stress exposure. In this sense, early environmental enrichment exposure (including exercise) and melatonin use in the perinatal period could be valuable in improving the negative consequences of early adversities. The evidence presented in this review encourages the realization of studies investigating the beneficial role of melatonin administration and environmental enrichment exposure in mitigating cognitive alteration in offspring under perinatal stress exposure. On the other hand, direct evidence of microbiota restoration as the main mechanism behind the beneficial effects of this treatment has not been fully demonstrated and should be explored in future studies.
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Affiliation(s)
- Mara Roxana Rubinstein
- Laboratorio de Psiconeuroendocrinoinmunologia, Instituto de Investigaciones Biomédicas, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)—Pontificia Universidad Católica Argentina, Buenos Aires C1107AFF, Argentina; (A.L.B.); (S.Q.); (M.R.W.)
| | | | | | | | - Ana María Genaro
- Laboratorio de Psiconeuroendocrinoinmunologia, Instituto de Investigaciones Biomédicas, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)—Pontificia Universidad Católica Argentina, Buenos Aires C1107AFF, Argentina; (A.L.B.); (S.Q.); (M.R.W.)
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Landreth K, Burgess M, Watson L, Lorusso JM, Grayson B, Harte MK, Neill JC. Handling prevents and reverses cognitive deficits induced by sub-chronic phencyclidine in a model for schizophrenia in rats. Physiol Behav 2023; 263:114117. [PMID: 36781093 DOI: 10.1016/j.physbeh.2023.114117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 01/23/2023] [Accepted: 02/09/2023] [Indexed: 02/13/2023]
Abstract
Treatments for schizophrenia are not effective in ameliorating cognitive deficits. Therefore, novel therapies are needed to treat cognitive impairments associated with schizophrenia (CIAS), which are modelled in rats through administration of sub-chronic phencyclidine (scPCP). We have previously shown that enrichment via voluntary exercise prevents and reverses impairments in novel object recognition (NOR) in this model. The present study aimed to investigate if handling could prevent delay-induced NOR deficits and prevent and reverse scPCP-induced NOR deficits. Two cohorts of adult female Lister Hooded rats were used. In experiment one, handling (five minutes/day, five days/week for two weeks), took place before scPCP administration (2 mg/kg, i.p. twice-daily for seven days). NOR tests were conducted at two, four, and seven weeks post-handling with a one-minute inter-trial interval (ITI) and at five weeks post-dosing with a six-hour ITI. In experiment two, rats were handled after scPCP administration and tested immediately in the one-minute ITI NOR task and again at two weeks post-handling. In both handling regimens, the scPCP control groups failed to discriminate novelty, conversely the scPCP handled groups significantly discriminated in this task. In the 6 h ITI test, vehicle control and scPCP control failed to discriminate novelty; however, the vehicle handled and scPCP handled groups did significantly discriminate. Handling rats prevented and reversed scPCP-induced deficits and prevented delay-induced NOR deficits. These findings add to evidence that environmental enrichment is a viable treatment for cognitive deficits in rodent tests and models of relevance to schizophrenia, with potential to translate into effective treatments for CIAS.
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Affiliation(s)
- K Landreth
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - M Burgess
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - L Watson
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - J M Lorusso
- Division of Evolution, Infection and Genomics, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - B Grayson
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom.
| | - M K Harte
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - J C Neill
- Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, United Kingdom; Medical Psychedelics Working Group, Drug Science, United Kingdom
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Landolfo E, Cutuli D, Decandia D, Balsamo F, Petrosini L, Gelfo F. Environmental Enrichment Protects against Neurotoxic Effects of Lipopolysaccharide: A Comprehensive Overview. Int J Mol Sci 2023; 24:ijms24065404. [PMID: 36982478 PMCID: PMC10049264 DOI: 10.3390/ijms24065404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/08/2023] [Accepted: 03/09/2023] [Indexed: 03/16/2023] Open
Abstract
Neuroinflammation is a pathophysiological condition associated with damage to the nervous system. Maternal immune activation and early immune activation have adverse effects on the development of the nervous system and cognitive functions. Neuroinflammation during adulthood leads to neurodegenerative diseases. Lipopolysaccharide (LPS) is used in preclinical research to mimic neurotoxic effects leading to systemic inflammation. Environmental enrichment (EE) has been reported to cause a wide range of beneficial changes in the brain. Based on the above, the purpose of the present review is to describe the effects of exposure to EE paradigms in counteracting LPS-induced neuroinflammation throughout the lifespan. Up to October 2022, a methodical search of studies in the literature, using the PubMed and Scopus databases, was performed, focusing on exposure to LPS, as an inflammatory mediator, and to EE paradigms in preclinical murine models. On the basis of the inclusion criteria, 22 articles were considered and analyzed in the present review. EE exerts sex- and age-dependent neuroprotective and therapeutic effects in animals exposed to the neurotoxic action of LPS. EE’s beneficial effects are present throughout the various ages of life. A healthy lifestyle and stimulating environments are essential to counteract the damages induced by neurotoxic exposure to LPS.
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Affiliation(s)
- Eugenia Landolfo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
| | - Debora Cutuli
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
| | - Davide Decandia
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Psychology, Sapienza University of Rome, Via dei Marsi 78, 00185 Rome, Italy
| | - Francesca Balsamo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Human Sciences, Guglielmo Marconi University, Via Plinio 44, 00193 Rome, Italy
| | - Laura Petrosini
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
| | - Francesca Gelfo
- IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
- Department of Human Sciences, Guglielmo Marconi University, Via Plinio 44, 00193 Rome, Italy
- Correspondence:
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Orchard ER, Rutherford HJV, Holmes AJ, Jamadar SD. Matrescence: lifetime impact of motherhood on cognition and the brain. Trends Cogn Sci 2023; 27:302-316. [PMID: 36609018 PMCID: PMC9957969 DOI: 10.1016/j.tics.2022.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 11/30/2022] [Accepted: 12/05/2022] [Indexed: 01/06/2023]
Abstract
Profound environmental, hormonal, and neurobiological changes mark the transition to motherhood as a major biosocial life event. Despite the ubiquity of motherhood, the enduring impact of caregiving on cognition and the brain across the lifespan is not well characterized and represents a unique window of opportunity to investigate human neural and cognitive development. By integrating insights from the human and animal maternal brain literatures with theories of cognitive ageing, we outline a framework for understanding maternal neural and cognitive changes across the lifespan. We suggest that the increased cognitive load of motherhood provides an initial challenge during the peripartum period, requiring continuous adaptation; yet when these demands are sustained across the lifespan, they result in increased late-life cognitive reserve.
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Affiliation(s)
- Edwina R Orchard
- Yale Child Study Center, School of Medicine, Yale University, New Haven, CT, USA; Department of Psychology, Faculty of Arts and Sciences, Yale University, New Haven, CT, USA.
| | | | - Avram J Holmes
- Department of Psychology, Faculty of Arts and Sciences, Yale University, New Haven, CT, USA
| | - Sharna D Jamadar
- Turner Institute of Brain and Mental Health & Monash Biomedical Imaging, Monash University, Melbourne, Australia
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Green MR, Swaney WT. Interacting effects of environmental enrichment across multiple generations on early life phenotypes in zebrafish. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B: MOLECULAR AND DEVELOPMENTAL EVOLUTION 2022. [DOI: 10.1002/jez.b.23184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 12/12/2022]
Affiliation(s)
- Michael R. Green
- School of Biological and Environmental Sciences Liverpool John Moores University Liverpool UK
- Chester Medical School University of Chester Chester UK
| | - William T. Swaney
- School of Biological and Environmental Sciences Liverpool John Moores University Liverpool UK
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The Molecular Effects of Environmental Enrichment on Alzheimer's Disease. Mol Neurobiol 2022; 59:7095-7118. [PMID: 36083518 PMCID: PMC9616781 DOI: 10.1007/s12035-022-03016-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/23/2022] [Indexed: 12/02/2022]
Abstract
Environmental enrichment (EE) is an environmental paradigm encompassing sensory, cognitive, and physical stimulation at a heightened level. Previous studies have reported the beneficial effects of EE in the brain, particularly in the hippocampus. EE improves cognitive function as well as ameliorates depressive and anxiety-like behaviors, making it a potentially effective neuroprotective strategy against neurodegenerative diseases such as Alzheimer's disease (AD). Here, we summarize the current evidence for EE as a neuroprotective strategy as well as the potential molecular pathways that can explain the effects of EE from a biochemical perspective using animal models. The effectiveness of EE in enhancing brain activity against neurodegeneration is explored with a view to differences present in early and late life EE exposure, with its potential application in human being discussed. We discuss EE as one of the non pharmacological approaches in preventing or delaying the onset of AD for future research.
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Kot M, Neglur PK, Pietraszewska A, Buzanska L. Boosting Neurogenesis in the Adult Hippocampus Using Antidepressants and Mesenchymal Stem Cells. Cells 2022; 11:cells11203234. [PMID: 36291101 PMCID: PMC9600461 DOI: 10.3390/cells11203234] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/06/2022] [Accepted: 10/12/2022] [Indexed: 11/16/2022] Open
Abstract
The hippocampus is one of the few privileged regions (neural stem cell niche) of the brain, where neural stem cells differentiate into new neurons throughout adulthood. However, dysregulation of hippocampal neurogenesis with aging, injury, depression and neurodegenerative disease leads to debilitating cognitive impacts. These debilitating symptoms deteriorate the quality of life in the afflicted individuals. Impaired hippocampal neurogenesis is especially difficult to rescue with increasing age and neurodegeneration. However, the potential to boost endogenous Wnt signaling by influencing pathway modulators such as receptors, agonists, and antagonists through drug and cell therapy-based interventions offers hope. Restoration and augmentation of hampered Wnt signaling to facilitate increased hippocampal neurogenesis would serve as an endogenous repair mechanism and contribute to hippocampal structural and functional plasticity. This review focuses on the possible interaction between neurogenesis and Wnt signaling under the control of antidepressants and mesenchymal stem cells (MSCs) to overcome debilitating symptoms caused by age, diseases, or environmental factors such as stress. It will also address some current limitations hindering the direct extrapolation of research from animal models to human application, and the technical challenges associated with the MSCs and their cellular products as potential therapeutic solutions.
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Affiliation(s)
- Marta Kot
- Correspondence: ; Tel.: +48-22-60-86-563
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15
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Manosso LM, Broseghini LDR, Campos JMB, Padilha APZ, Botelho MEM, da Costa MA, Abelaira HM, Gonçalves CL, Réus GZ. Beneficial effects and neurobiological aspects of environmental enrichment associated to major depressive disorder and autism spectrum disorder. Brain Res Bull 2022; 190:152-167. [PMID: 36191730 DOI: 10.1016/j.brainresbull.2022.09.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 09/26/2022] [Accepted: 09/28/2022] [Indexed: 11/15/2022]
Abstract
A suitable enriched environment favors development but can also influence behavior and neuronal circuits throughout development. Studies have shown that environmental enrichment (EE) can be used as an essential tool or combined with conventional treatments to improve psychiatric and neurological symptoms, including major depressive disorder (MDD) and autism spectrum disorder (ASD). Both disorders affect a significant percentage of the world's population and have complex pathophysiology. Moreover, the available treatments for MDD and ASD are still inadequate for many affected individuals. Experimental models demonstrate that EE has significant positive effects on behavioral modulation. In addition, EE has effects on neurobiology, including improvement in synaptic connections and neuroplasticity, modulation of neurotransmissions, a decrease in inflammation and oxidative stress, and other neurobiology effects that can be involved in the pathophysiology of MDD and ASD. Thus, this review aims to describe the leading behavioral and neurobiological effects associated with EE in MDD and ASD.
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Affiliation(s)
- Luana M Manosso
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Lia D R Broseghini
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - José Marcelo B Campos
- Experimental Neurology Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Alex Paulo Z Padilha
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Maria Eduarda M Botelho
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Maiara A da Costa
- Experimental Neurology Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Helena M Abelaira
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Cinara L Gonçalves
- Experimental Neurology Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil
| | - Gislaine Z Réus
- Translational Psychiatry Laboratory, Graduate Program in Health Sciences, University of Southern Santa Catarina (UNESC), Criciúma, SC, Brazil.
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16
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Balietti M, Conti F. Environmental enrichment and the aging brain: is it time for standardization? Neurosci Biobehav Rev 2022; 139:104728. [PMID: 35691473 DOI: 10.1016/j.neubiorev.2022.104728] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 05/01/2022] [Accepted: 06/06/2022] [Indexed: 11/30/2022]
Abstract
Aging entails a progressive decline of cognitive abilities. However, since the brain is endowed with considerable plasticity, adequate stimulation can delay or partially compensate for age-related structural and functional impairment. Environmental enrichment (EE) has been reported to determine a wide range of cerebral changes. Although most findings have been obtained in young and adult animals, research has recently turned to aged individuals. Notably, EE can contribute identifying key lifestyle factors whose change can help extend the "mind-span", i.e., the time an individual lives in a healthy cognitive condition. Here we discuss specific methodological issues that can affect the outcomes of EE interventions applied to aged rodents, summarize the main variables that would need standardization (e.g., timing and duration, enrichment items, control animals and setting), and offer some suggestions on how this goal may be achieved. Reaching a consensus on EE experiment design would significantly reduce differences between and within laboratories, enable constructive discussions among researchers, and improve data interpretation.
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Affiliation(s)
- Marta Balietti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy.
| | - Fiorenzo Conti
- Center for Neurobiology of Aging, IRCCS INRCA, Ancona, Italy; Section of Neuroscience and Cell Biology, Department of Experimental and Clinical Medicine, Università Politecnica delle Marche, Ancona, Italy.
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17
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Cabrera-Muñoz EA, Olvera-Hernández S, Vega-Rivera NM, Meneses-San Juan D, Reyes-Haro D, Ortiz-López L, Ramírez Rodríguez GB. Environmental Enrichment Differentially Activates Neural Circuits in FVB/N Mice, Inducing Social Interaction in Females but Agonistic Behavior in Males. Neurochem Res 2022; 47:781-794. [PMID: 34978003 DOI: 10.1007/s11064-021-03487-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 10/14/2021] [Accepted: 11/09/2021] [Indexed: 01/17/2023]
Abstract
Environmental enrichment induces behavioral and structural modifications in rodents and influences the capability of mice to cope with stress. However, little is understood about hippocampal neurogenesis and the appearance of social/agonistic (aggressive) behavior upon activation of different neuronal circuits in FVB/N mice. Thus, in this study we hypothesized that environmental enrichment differentially regulates neurogenesis, neural circuit activation and social/agonistic behavior in male and female FVB/N mice. We explored the (1) neurogenic process as an indicative of neuroplasticity, (2) neuronal activation in the limbic system, and (3) social behavior using the resident-intruder test. On postnatal day 23 (PD23), mice were assigned to one of two groups: Standard Housing or Environmental Enrichment. At PD53, rodents underwent the resident-intruder test to evaluate social behaviors. Results revealed that environmental enrichment increased neurogenesis and social interaction in females. In males, environmental enrichment increased neurogenesis and agonistic behavior. Enriched male mice expressed higher levels of agonistic-related behavior than female mice housed under the same conditions. Neural circuit analysis showed lower activation in the amygdala of enriched males and higher activation in enriched females than their respective controls. Enriched females also showed higher activation in the frontal cortex without differences in male groups. Moreover, the insular cortex was less activated in females than in males. Thus, our results indicate that environmental enrichment has different effects on neuroplasticity and social/agonistic behavior in FVB/N mice, suggesting the relevance of sexual dimorphism in response to environmental stimuli.
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Affiliation(s)
- Edith Araceli Cabrera-Muñoz
- Laboratorio of Neurogénesis, Subdirección de Investigaciones Clínicas, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco No. 101, Colonia San Lorenzo Huipulco, Delegación Tlalpan, C.P. 14370, México City, México
| | - Sandra Olvera-Hernández
- Laboratorio of Neurogénesis, Subdirección de Investigaciones Clínicas, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco No. 101, Colonia San Lorenzo Huipulco, Delegación Tlalpan, C.P. 14370, México City, México
| | - Nelly Maritza Vega-Rivera
- Laboratorio of Neuropsicofarmacología, Dirección de Neurociencias, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco 101, C.P. 14370, México City, México
| | - David Meneses-San Juan
- Laboratorio of Neurogénesis, Subdirección de Investigaciones Clínicas, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco No. 101, Colonia San Lorenzo Huipulco, Delegación Tlalpan, C.P. 14370, México City, México
| | - Daniel Reyes-Haro
- Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología. Universidad Nacional Autónoma de México, Campus Juriquilla. Boulevard Juriquilla 3001, C.P. 76230, Juriquilla, Querétaro, México
| | - Leonardo Ortiz-López
- Laboratorio of Neurogénesis, Subdirección de Investigaciones Clínicas, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco No. 101, Colonia San Lorenzo Huipulco, Delegación Tlalpan, C.P. 14370, México City, México
| | - Gerardo Bernabé Ramírez Rodríguez
- Laboratorio of Neurogénesis, Subdirección de Investigaciones Clínicas, Instituto Nacional de Psiquiatría "Ramón de La Fuente Muñiz", Calzada México-Xochimilco No. 101, Colonia San Lorenzo Huipulco, Delegación Tlalpan, C.P. 14370, México City, México.
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18
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Brusini I, MacNicol E, Kim E, Smedby Ö, Wang C, Westman E, Veronese M, Turkheimer F, Cash D. MRI-derived brain age as a biomarker of ageing in rats: validation using a healthy lifestyle intervention. Neurobiol Aging 2022; 109:204-215. [PMID: 34775211 DOI: 10.1016/j.neurobiolaging.2021.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/06/2021] [Accepted: 10/08/2021] [Indexed: 12/21/2022]
Abstract
The difference between brain age predicted from MRI and chronological age (the so-called BrainAGE) has been proposed as an ageing biomarker. We analyse its cross-species potential by testing it on rats undergoing an ageing modulation intervention. Our rat brain age prediction model combined Gaussian process regression with a classifier and achieved a mean absolute error (MAE) of 4.87 weeks using cross-validation on a longitudinal dataset of 31 normal ageing rats. It was then tested on two groups of 24 rats (MAE = 9.89 weeks, correlation coefficient = 0.86): controls vs. a group under long-term environmental enrichment and dietary restriction (EEDR). Using a linear mixed-effects model, BrainAGE was found to increase more slowly with chronological age in EEDR rats (p=0.015 for the interaction term). Cox regression showed that older BrainAGE at 5 months was associated with higher mortality risk (p=0.03). Our findings suggest that lifestyle-related prevention approaches may help to slow down brain ageing in rodents and the potential of BrainAGE as a predictor of age-related health outcomes.
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Affiliation(s)
- Irene Brusini
- Department of Biomedical Engineering and Health Systems,KTH Royal Institute of Technology, Stockholm, Sweden; Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden.
| | - Eilidh MacNicol
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Eugene Kim
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Örjan Smedby
- Department of Biomedical Engineering and Health Systems,KTH Royal Institute of Technology, Stockholm, Sweden
| | - Chunliang Wang
- Department of Biomedical Engineering and Health Systems,KTH Royal Institute of Technology, Stockholm, Sweden
| | - Eric Westman
- Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Stockholm, Sweden
| | - Mattia Veronese
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom; Department of Information Engineering, University of Padua, Padua, Italy
| | - Federico Turkheimer
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
| | - Diana Cash
- Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom
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Short Daily Exposure to Environmental Enrichment, Fluoxetine, or Their Combination Reverses Deterioration of the Coat and Anhedonia Behaviors with Differential Effects on Hippocampal Neurogenesis in Chronically Stressed Mice. Int J Mol Sci 2021; 22:ijms222010976. [PMID: 34681636 PMCID: PMC8535985 DOI: 10.3390/ijms222010976] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/10/2021] [Accepted: 08/10/2021] [Indexed: 11/16/2022] Open
Abstract
Depression is a neuropsychiatric disorder with a high impact on the worldwide population. To overcome depression, antidepressant drugs are the first line of treatment. However, pre-clinical studies have pointed out that antidepressants are not entirely efficacious and that the quality of the living environment after stress cessation may play a relevant role in increasing their efficacy. As it is unknown whether a short daily exposure to environmental enrichment during chronic stress and antidepressant treatment will be more effective than just the pharmacological treatment, this study analyzed the effects of fluoxetine, environmental enrichment, and their combination on depressive-associated behavior. Additionally, we investigated hippocampal neurogenesis in mice exposed to chronic mild stress. Our results indicate that fluoxetine reversed anhedonia. Besides, fluoxetine reversed the decrement of some events of the hippocampal neurogenic process caused by chronic mild stress. Conversely, short daily exposure to environmental enrichment changed the deterioration of the coat and anhedonia. Although, this environmental intervention did not produce significant changes in the neurogenic process affected by chronic mild stress, fluoxetine plus environmental enrichment showed similar effects to those caused by environmental enrichment to reverse depressive-like behaviors. Like fluoxetine, the combination reversed the declining number of Ki67, doublecortin, calretinin cells and mature newborn neurons. Finally, this study suggests that short daily exposure to environmental enrichment improves the effects of fluoxetine to reverse the deterioration of the coat and anhedonia in chronically stressed mice. In addition, the combination of fluoxetine with environmental enrichment produces more significant effects than those caused by fluoxetine alone on some events of the neurogenic process. Thus, environmental enrichment improves the benefits of pharmacological treatment by mechanisms that need to be clarified.
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20
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Grigoryan GA. Molecular-Cellular Mechanisms of Plastic Restructuring Produced by an Enriched Environment. Effects on Learning and Memory. NEUROCHEM J+ 2021. [DOI: 10.1134/s1819712421030041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Song MK, Kim YJ, Kim SH, Yeo SG, Kim YJ. Environmental enrichment modulates silent information regulator 1 (SIRT1) activity to attenuate central presbycusis in a rat model of normal aging. Exp Gerontol 2021; 155:111552. [PMID: 34530105 DOI: 10.1016/j.exger.2021.111552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/21/2021] [Accepted: 08/31/2021] [Indexed: 11/15/2022]
Abstract
Age-related hearing loss (ARHL) is sensory impairment in the elderly. This study aimed to identify a critical molecular mechanism that can maintain young phenotypes. We focused on the effect of exposure to environmental enrichment (EE) for 12 weeks in the central auditory pathway and limbic system of aged rats. The effects of EE were compared with the effects of dexamethasone administration. We found that in 74-week-old rats hearing function was significantly reduced and the number of neuronal specific nuclear protein (NeuN)-positive cells was decreased by 10-15% in the auditory cortex, amygdala, and hippocampus. EE exposure did not significantly affect the number of neurons, but DX administration significantly decreased their numbers in the amygdala compared with untreated aged rats. Both treatments reduced inducible nitric oxide synthase (iNOS) expression in the auditory pathway and limbic system. Exposure to EE significantly increased silent information regulator 1 (SIRT1) expression and activity, and nicotinamide phosphoribosyltransferase (NAMPT) concentration. In this study, the exposure to EE resulted in attenuated age-related hearing loss accompanied by reduction of iNOS expression and increase SIRT1 activity and NAMPT level. These data showed that EE may be a potential therapeutic to prevent ARHL.
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Affiliation(s)
- Min Kyung Song
- Department of Nursing, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Yoon Ju Kim
- Department of Nursing, Graduate School, Kyung Hee University, Seoul, Republic of Korea
| | - Sang Hoon Kim
- Department of Otorhinolaryngology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Seung Geun Yeo
- Department of Otorhinolaryngology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea.
| | - Youn-Jung Kim
- College of Nursing Science, Kyung Hee University·East-West Nursing Research Institute, Seoul, Republic of Korea.
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22
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Lambert CT, Guillette LM. The impact of environmental and social factors on learning abilities: a meta-analysis. Biol Rev Camb Philos Soc 2021; 96:2871-2889. [PMID: 34342125 DOI: 10.1111/brv.12783] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 12/20/2022]
Abstract
Since the 1950s, researchers have examined how differences in the social and asocial environment affect learning in rats, mice, and, more recently, a variety of other species. Despite this large body of research, little has been done to synthesize these findings and to examine if social and asocial environmental factors have consistent effects on cognitive abilities, and if so, what aspects of these factors have greater or lesser impact. Here, we conducted a systematic review and meta-analysis examining how different external environmental features, including the social environment, impact learning (both speed of acquisition and performance). Using 531 mean-differences from 176 published articles across 27 species (with studies on rats and mice being most prominent) we conducted phylogenetically corrected mixed-effects models that reveal: (i) an average absolute effect size |d| = 0.55 and directional effect size d = 0.34; (ii) interventions manipulating the asocial environment result in larger effects than social interventions alone; and (iii) the length of the intervention is a significant predictor of effect size, with longer interventions resulting in larger effects. Additionally, much of the variation in effect size remained unexplained, possibly suggesting that species differ widely in how they are affected by environmental interventions due to varying ecological and evolutionary histories. Overall our results suggest that social and asocial environmental factors do significantly affect learning, but these effects are highly variable and perhaps not always as predicted. Most notably, the type (social or asocial) and length of interventions are important in determining the strength of the effect.
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Affiliation(s)
- Connor T Lambert
- Department of Psychology, University of Alberta, P217 Biological Sciences Building, Edmonton, AB, T6G 2R3, Canada
| | - Lauren M Guillette
- Department of Psychology, University of Alberta, P217 Biological Sciences Building, Edmonton, AB, T6G 2R3, Canada
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23
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Stark CEL, Clemenson GD, Aluru U, Hatamian N, Stark SM. Playing Minecraft Improves Hippocampal-Associated Memory for Details in Middle Aged Adults. Front Sports Act Living 2021; 3:685286. [PMID: 34291204 PMCID: PMC8287053 DOI: 10.3389/fspor.2021.685286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/08/2021] [Indexed: 11/13/2022] Open
Abstract
Concerns are often raised about the impact that playing video games may have on cognition and behavior, whether gameplay is intense and protracted as with competitive Esports or whether it is more casual gameplay. Work in our lab and others, however, has shown that at least some classes of games can improve memory function. In particular, playing immersive 3D games that provide rich experiences and novelty improve memory on tasks that rely upon the hippocampus in effects that mirror the effects of “environmental enrichment” in numerous rodent studies. Our goal in the present study was to determine whether even modest amounts of gameplay (~30 min/day for 4 weeks) would result in improved memory performance in middle-aged adults. Not only is this demographic potentially highly receptive to gaming (they make up a significant portion of Esports viewers and of game players), but interventions in middle age may be a prime time for reducing later age-related cognitive decline. Here, we found that the benefits in middle age paralleled effects previously observed in young adults as playing Minecraft, showing improved memory performance on a hippocampal dependent memory task.
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Affiliation(s)
- Craig E L Stark
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Gregory D Clemenson
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Ujwal Aluru
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Nikki Hatamian
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
| | - Shauna M Stark
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, United States
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24
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Zocher S, Overall RW, Lesche M, Dahl A, Kempermann G. Environmental enrichment preserves a young DNA methylation landscape in the aged mouse hippocampus. Nat Commun 2021; 12:3892. [PMID: 34162876 PMCID: PMC8222384 DOI: 10.1038/s41467-021-23993-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 05/20/2021] [Indexed: 02/05/2023] Open
Abstract
The decline of brain function during aging is associated with epigenetic changes, including DNA methylation. Lifestyle interventions can improve brain function during aging, but their influence on age-related epigenetic changes is unknown. Using genome-wide DNA methylation sequencing, we here show that experiencing a stimulus-rich environment counteracts age-related DNA methylation changes in the hippocampal dentate gyrus of mice. Specifically, environmental enrichment prevented the aging-induced CpG hypomethylation at target sites of the methyl-CpG-binding protein Mecp2, which is critical to neuronal function. The genes at which environmental enrichment counteracted aging effects have described roles in neuronal plasticity, neuronal cell communication and adult hippocampal neurogenesis and are dysregulated with age-related cognitive decline in the human brain. Our results highlight the stimulating effects of environmental enrichment on hippocampal plasticity at the level of DNA methylation and give molecular insights into the specific aspects of brain aging that can be counteracted by lifestyle interventions.
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Affiliation(s)
- Sara Zocher
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Rupert W Overall
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Mathias Lesche
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
- DRESDEN-concept Genome Center c/o Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Dresden, Germany
| | - Andreas Dahl
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
- DRESDEN-concept Genome Center c/o Center for Molecular and Cellular Bioengineering (CMCB), Technische Universität Dresden, Dresden, Germany
| | - Gerd Kempermann
- German Center for Neurodegenerative Diseases (DZNE) Dresden, Dresden, Germany.
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.
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25
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Huang H, Wang Q, Guan X, Zhang X, Zhang Y, Cao J, Li X. Effects of enriched environment on depression and anxiety-like behavior induced by early life stress: A comparison between different periods. Behav Brain Res 2021; 411:113389. [PMID: 34058267 DOI: 10.1016/j.bbr.2021.113389] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND Brain development is a prolonged process and it is sensitive to the environment during critical periods. Stress in early life is believed to increase vulnerability to depression, while enriched environment (EE) has beneficial effects on neural plasticity and depression. In this study, we compared the therapeutic effect of EE during different periods on early life stress-induced depression, and investigated the role of brain-derived neurotrophic factor (BDNF) and protein kinase B (AKT) on the effect of EE. Plasma corticosterone level was also detected to evaluate the reactivity of hypothalamic-pituitary-adrenal axis. METHODS C57BL/6 mice were subjected to a 4-h maternal separation (MS) procedure during postnatal days 2-21. After this separation, the mice were assigned to standard environment groups (SE), EE in the early period groups (3-8 weeks, EEE) and EE in the adult groups (8-13 weeks, EEA). Depression and anxiety behavior were evaluated at 14-weeks of age. The plasma corticosterone was quantified utilizing enzyme-linked immunosorbent assay. Hippocampus BDNF and AKT/p-AKT were detected using Western blotting. RESULTS The results showed that MS increased depression and anxiety level, while EE in both intervention periods alleviated the symptoms of depression and anxiety. The EEE group showed better effects in terms of anhedonia and anxiety than the EEA group. The difference in despair behavior between the EEE and EEA groups was not significant. MS increased plasma corticosterone level, while EE decreased corticosterone level in both intervention periods. EE increased BDNF and p-AKT expression in the hippocampus, with stronger effects in the EEE group. CONCLUSION EE during the early development period was more effective in alleviating depression and anxiety induced by early life stress. BDNF and AKT may play a significant role in the effect of EE, and further research is needed to explore the detailed neurobiological mechanisms.
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Affiliation(s)
- Hongfei Huang
- Department of Psychiatry, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, China; Department of Psychiatry, General Hospital of Northern Theater Command, Shenyang, Liaoning, 110001, China
| | - Qi Wang
- Department of Psychiatry, General Hospital of Northern Theater Command, Shenyang, Liaoning, 110001, China
| | - Xiaofeng Guan
- Department of Psychiatry, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, China
| | - Xia Zhang
- Department of Psychiatry, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, China
| | - Yihan Zhang
- Department of Psychiatry, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, China
| | - Jinlong Cao
- Department of Psychiatry, The Fourth Hospital of Haining People, Jiaxing, Zhejiang, China
| | - Xiaobai Li
- Department of Psychiatry, The First Hospital of China Medical University, Shenyang, Liaoning, 110001, China.
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Espeso-Gil S, Holik AZ, Bonnin S, Jhanwar S, Chandrasekaran S, Pique-Regi R, Albaigès-Ràfols J, Maher M, Permanyer J, Irimia M, Friedländer MR, Pons-Espinal M, Akbarian S, Dierssen M, Maass PG, Hor CN, Ossowski S. Environmental Enrichment Induces Epigenomic and Genome Organization Changes Relevant for Cognition. Front Mol Neurosci 2021; 14:664912. [PMID: 34025350 PMCID: PMC8131874 DOI: 10.3389/fnmol.2021.664912] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Accepted: 04/09/2021] [Indexed: 01/11/2023] Open
Abstract
In early development, the environment triggers mnemonic epigenomic programs resulting in memory and learning experiences to confer cognitive phenotypes into adulthood. To uncover how environmental stimulation impacts the epigenome and genome organization, we used the paradigm of environmental enrichment (EE) in young mice constantly receiving novel stimulation. We profiled epigenome and chromatin architecture in whole cortex and sorted neurons by deep-sequencing techniques. Specifically, we studied chromatin accessibility, gene and protein regulation, and 3D genome conformation, combined with predicted enhancer and chromatin interactions. We identified increased chromatin accessibility, transcription factor binding including CTCF-mediated insulation, differential occupancy of H3K36me3 and H3K79me2, and changes in transcriptional programs required for neuronal development. EE stimuli led to local genome re-organization by inducing increased contacts between chromosomes 7 and 17 (inter-chromosomal). Our findings support the notion that EE-induced learning and memory processes are directly associated with the epigenome and genome organization.
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Affiliation(s)
- Sergio Espeso-Gil
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- Genetics and Genome Biology Program, SickKids Research Institute, Toronto, ON, Canada
| | - Aliaksei Z. Holik
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Sarah Bonnin
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Shalu Jhanwar
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Sandhya Chandrasekaran
- MD/PhD Program in the Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, United States
- Department of Psychiatry and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Roger Pique-Regi
- Center for Molecular Medicine and Genetics, Wayne State University, Detroit, MI, United States
| | - Júlia Albaigès-Ràfols
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Michael Maher
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Jon Permanyer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Manuel Irimia
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
- ICREA, Pg. Lluis Companys 23, Barcelona, Spain
| | - Marc R. Friedländer
- Science for Life Laboratory, Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Meritxell Pons-Espinal
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Schahram Akbarian
- Department of Psychiatry and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Mara Dierssen
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Philipp G. Maass
- Genetics and Genome Biology Program, SickKids Research Institute, Toronto, ON, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Charlotte N. Hor
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Stephan Ossowski
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
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Karoglu-Eravsar ET, Tuz-Sasik MU, Adams MM. Environmental enrichment applied with sensory components prevents age-related decline in synaptic dynamics: Evidence from the zebrafish model organism. Exp Gerontol 2021; 149:111346. [PMID: 33838219 DOI: 10.1016/j.exger.2021.111346] [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: 01/24/2021] [Revised: 03/31/2021] [Accepted: 04/03/2021] [Indexed: 10/21/2022]
Abstract
Progression of cognitive decline with or without neurodegeneration varies among elderly subjects. The main aim of the current study was to illuminate the molecular mechanisms that promote and retain successful aging in the context of factors such as environment and gender, both of which alter the resilience of the aging brain. Environmental enrichment (EE) is one intervention that may lead to the maintenance of cognitive processing at older ages in both humans and animal subjects. EE is easily applied to different model organisms, including zebrafish, which show similar age-related molecular and behavioral changes as humans. Global changes in cellular and synaptic markers with respect to age, gender and 4-weeks of EE applied with sensory stimulation were investigated using the zebrafish model organism. Results indicated that EE increases brain weight in an age-dependent manner without affecting general body parameters like body mass index (BMI). Age-related declines in the presynaptic protein synaptophysin, AMPA-type glutamate receptor subunits and a post-mitotic neuronal marker were observed and short-term EE prevents these changes in aged animals, as well as elevates levels of the inhibitory scaffolding protein, gephyrin. Gender-driven alterations were observed in the levels of the glutamate receptor subunits. Oxidative stress markers were significantly increased in the old animals, while exposure to EE did not alter this pattern. These data suggest that EE with sensory stimulation exerts its effects mainly on age-related changes in synaptic dynamics, which likely increase brain resilience through specific cellular mechanisms.
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Affiliation(s)
- Elif Tugce Karoglu-Eravsar
- Interdisciplinary Program in Neuroscience, Aysel Sabuncu Brain Research Center, Bilkent University, Ankara, Turkey; National Nanotechnology Research Center (UNAM), Bilkent University, Ankara, Turkey; Department of Molecular Biology and Genetics, Zebrafish Facility, Bilkent University, Ankara, Turkey; Department of Psychology, Selcuk University, Konya, Turkey
| | - Melek Umay Tuz-Sasik
- Interdisciplinary Program in Neuroscience, Aysel Sabuncu Brain Research Center, Bilkent University, Ankara, Turkey; National Nanotechnology Research Center (UNAM), Bilkent University, Ankara, Turkey; Department of Molecular Biology and Genetics, Zebrafish Facility, Bilkent University, Ankara, Turkey
| | - Michelle M Adams
- Interdisciplinary Program in Neuroscience, Aysel Sabuncu Brain Research Center, Bilkent University, Ankara, Turkey; National Nanotechnology Research Center (UNAM), Bilkent University, Ankara, Turkey; Department of Molecular Biology and Genetics, Zebrafish Facility, Bilkent University, Ankara, Turkey; Department of Psychology, Bilkent University, Ankara, Turkey.
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Early environmental enrichment rescues memory impairments provoked by mild neonatal hypoxia-ischemia in adolescent mice. Behav Brain Res 2021; 407:113237. [PMID: 33798820 DOI: 10.1016/j.bbr.2021.113237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 01/28/2021] [Accepted: 03/08/2021] [Indexed: 12/27/2022]
Abstract
Hypoxia-ischemia (HI) is a consequence of a lack of oxygen and glucose support to the developing brain, which causes several neurodevelopmental impairments. Environmental enrichment (EE) is considered an option to recover the alterations observed in rodents exposed to HI. The aim of this study was to investigate the impact of early EE on memory, hippocampal volume and brain-derived neurotrophic factor (Bbnf) and glucocorticoid receptor (Nr3c1) gene expression of mice exposed to HI. At P10, pups underwent right carotid artery permanent occlusion followed by 35 min of 8% O2 hypoxic environment. Starting at P11, animals were reared in EE or in standard cage (HI-SC or SHAM-SC) conditions until behavioral testing (P45). SHAM pups did not undergo carotid ligation and hypoxic exposure. Memory performance was assessed in the Y-maze, Novel object recognition, and Barnes maze. Animals were then sacrificed for analysis of hippocampal volume and Bdnf and Nr3c1 gene expression. We observed that animals exposed to HI performed worse in all three tests compared to SHAM animals. Furthermore, HI animals exposed to EE did not differ from SHAM animals in all tasks. Moreover, HI decreased hippocampal volume, while animals reared in early EE were not different compared to SHAM animals. Animals exposed to HI also showed upregulated hippocampal Bdnf expression compared to SHAM animals. We conclude that early EE from P11 to P45 proved to be effective in recovering memory impairments and hippocampal volume loss elicited by HI. Nevertheless, Bdnf expression was not associated with the improvements in memory performance observed in animals exposed to EE after a hypoxic-ischemic event.
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Zentall TR. Effect of Environmental Enrichment on the Brain and on Learning and Cognition by Animals. Animals (Basel) 2021; 11:ani11040973. [PMID: 33807367 PMCID: PMC8066627 DOI: 10.3390/ani11040973] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 01/12/2023] Open
Abstract
Simple Summary Most people consider the environment in which animals are kept to be an ethical matter, separate from the research that we conduct with them. Those of us who do research on the cognitive behavior of animals try to consider their welfare, but what we often fail to recognize is that the welfare of the animals we study can affect the results of experiments that we investigate. We have but scratched the surface of the question, how do enriched environments affect the cognitive behavior of animals, in our case pigeons. We have found that pigeons with experience in an enriched environment are less impulsive. The reduction in impulsivity results in a reduced tendency to make the suboptimal choice. It also has been claimed to make animals more optimistic, as assessed by their tendency to make choices of more favorable alternatives, under ambiguous conditions. Abstract The humane treatment of animals suggests that they should be housed in an environment that is rich in stimulation and allows for varied activities. However, even if one’s main concern is an accurate assessment of their learning and cognitive abilities, housing them in an enriched environment can have an important effect on the assessment of those abilities. Research has found that the development of the brain of animals is significantly affected by the environment in which they live. Not surprisingly, their ability to learn both simple and complex tasks is affected by even modest time spent in an enriched environment. In particular, animals that are housed in an enriched environment are less impulsive and make more optimal choices than animals housed in isolation. Even the way that they judge the passage of time is affected by their housing conditions. Some researchers have even suggested that exposing animals to an enriched environment can make them more “optimistic” in how they treat ambiguous stimuli. Whether that behavioral effect reflects the subtlety of differences in optimism/pessimism or something simpler, like differences in motivation, incentive, discriminability, or neophobia, it is clear that the conditions of housing can have an important effect on the learning and cognition of animals.
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Affiliation(s)
- Thomas R Zentall
- Department of Psychology, University of Kentucky, Lexington, KY 40506-0044, USA
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Zhao Y, Yang Z, He Y, Sun R, Yuan H. The KATP channel opener, nicorandil, ameliorates brain damage by modulating synaptogenesis after ischemic stroke. PLoS One 2021; 16:e0246019. [PMID: 33497397 PMCID: PMC7837460 DOI: 10.1371/journal.pone.0246019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/12/2021] [Indexed: 12/25/2022] Open
Abstract
With population growth and aging, more and more patients with cerebral infarction have varying degrees of disability. ATP-sensitive potassium (KATP) channels regulate many cellular functions by coupling metabolic status with cell membrane electrical activity. Nicorandil (N-(2-hydroxyethyl)-nicotinamide nitrate) is the first KATP channel opener approved for clinical use. It has been reported that it might exert protective effects on the cerebral infarction by increasing cerebral blood flow and reducing inflammation. However, only a few studies explored its role in synaptogenesis. We made the rat model of middle cerebral artery occlusion (MCAO). Nicorandil was administered to rats via oral administration immediately after the surgery at a dose of 7.5 mg/kg and then daily for the next days. Infarct volume, cerebral edema, neurological deficits, cognitive impairment, and the level of Synaptophysin (SYP)、Growth associated protein-43 (GAP43) and neuronal nuclear antigen (NeuN) levels were measured to evaluate the effect of nicorandil. Our data showed that nicorandil treatment could decrease brain damage, improve learning and memory, and increase SYP、GAP43 and NeuN level. Taken together, we propose that nicorandil, as an opener of the KATP channel, provides a neuroprotective role in MCAO by promoting synaptic connections.
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Affiliation(s)
- Yuanzheng Zhao
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- * E-mail:
| | - Zhuoying Yang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yuanhong He
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Ruonan Sun
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Heping Yuan
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
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Enriched Environment Minimizes Anxiety/Depressive-Like Behavior in Rats Exposed to Immobilization Stress and Augments Hippocampal Neurogenesis (In Vitro). J Mol Neurosci 2021; 71:2071-2084. [PMID: 33492617 DOI: 10.1007/s12031-021-01798-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/12/2021] [Indexed: 10/22/2022]
Abstract
Chronic exposure to stress disturbs the homeostasis of the brain, thus, deleteriously affecting the neurological circuits. In literature, there are investigations about the stress-related alterations in behavioral response and adult neurogenesis; however, an effective combating strategy to evade stress is still at stake. Hence, the present study is designed to investigate the effect of an enriched environment in alleviating the anxiety/depressive-like behavioral response and enhancing the adult neurogenesis in the hippocampal region of rats exposed to chronic immobilization stress. The rats were exposed to chronic immobilization stress (IS) for 4 h/day followed by the enriched environment (EE) for 2 h/day for 28 days, and finally, the hippocampal region was dissected out after the behavioral analyses. IS group showed increased behavioral despair to tail suspension test, decrement in the activity for light/dark box test, and less grooming activity towards splash test. In contrast, IS + EE rats exhibited a decrease in the activity of tail suspension test and an increase in the behavioral response to light/dark box test and splash test. The in vitro assessment of primary cultures of neurospheres from the IS group resulted in decreased levels of proliferation in the cell number and metabolic activity of both MTT assay and lactate levels. IS + EE group revealed an increase in the growth curve of neurospheres and higher metabolic activities of MTT and lactate. The IS cultures had reduced neurite length, while the neurite outgrowths were increased in IS + EE group. The IS group showed significant reduction in the protein and mRNA levels of nestin, GFAP, CD11b, MOG, and synaptophysin, whereas the IS + EE cultures exhibited significant increase in the levels of these stem cell markers. Our data highlight the positive impact of EE against stress-related behavioral changes in rats exposed to chronic immobilization stress perhaps by interfering with the differentiation of neurospheres and neurogenesis.
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32
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McQuail JA, Dunn AR, Stern Y, Barnes CA, Kempermann G, Rapp PR, Kaczorowski CC, Foster TC. Cognitive Reserve in Model Systems for Mechanistic Discovery: The Importance of Longitudinal Studies. Front Aging Neurosci 2021; 12:607685. [PMID: 33551788 PMCID: PMC7859530 DOI: 10.3389/fnagi.2020.607685] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/30/2020] [Indexed: 12/14/2022] Open
Abstract
The goal of this review article is to provide a resource for longitudinal studies, using animal models, directed at understanding and modifying the relationship between cognition and brain structure and function throughout life. We propose that forthcoming longitudinal studies will build upon a wealth of knowledge gleaned from prior cross-sectional designs to identify early predictors of variability in cognitive function during aging, and characterize fundamental neurobiological mechanisms that underlie the vulnerability to, and the trajectory of, cognitive decline. Finally, we present examples of biological measures that may differentiate mechanisms of the cognitive reserve at the molecular, cellular, and network level.
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Affiliation(s)
- Joseph A McQuail
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC, United States
| | - Amy R Dunn
- The Jackson Laboratory, Bar Harbor, ME, United States
| | - Yaakov Stern
- Cognitive Neuroscience Division, Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, United States
| | - Carol A Barnes
- Departments of Psychology and Neuroscience, University of Arizona, Tucson, AZ, United States.,Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, United States
| | - Gerd Kempermann
- CRTD-Center for Regenerative Therapies Dresden, Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Helmholtz Association of German Research Centers (HZ), Dresden, Germany
| | - Peter R Rapp
- Laboratory of Behavioral Neuroscience, Neurocognitive Aging Section, National Institute on Aging, Baltimore, MD, United States
| | | | - Thomas C Foster
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL, United States.,Genetics and Genomics Program, University of Florida, Gainesville, FL, United States
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33
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Rizzolo L, Leger M, Corvaisier S, Groussard M, Platel H, Bouet V, Schumann-Bard P, Freret T. Long-Term Music Exposure Prevents Age-Related Cognitive Deficits in Rats Independently of Hippocampal Neurogenesis. Cereb Cortex 2021; 31:620-634. [PMID: 32959057 DOI: 10.1093/cercor/bhaa247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 08/05/2020] [Accepted: 08/11/2020] [Indexed: 11/14/2022] Open
Abstract
Cognitive decline appears across aging. While some studies report beneficial effects of musical listening and practice on cognitive aging, the underlying neurobiological mechanisms remain unknown. This study aims to determine whether chronic (6 h/day, 3 times/week) and long-lasting (4-8 months) music exposure, initiated at middle age in rats (15 months old), can influence behavioral parameters sensitive to age effects and reduce age-related spatial memory decline in rats. Spontaneous locomotor, circadian rhythmic activity, and anxiety-like behavior as well as spatial working and reference memory were assessed in 14-month-old rats and then after 4 and 8 months of music exposure (19 and 23 months old, respectively). Spatial learning and reference memory data were followed up by considering cognitive status of animals prior to music exposure (14 months old) given by K-means clustering of individual Z-score. Hippocampal cell proliferation and brain-derived neurotrophic factor (BDNF) level in the hippocampus and frontal cortex were measured. Results show that music exposure differentially rescues age-related deficits in spatial navigation tasks according to its duration without affecting spontaneous locomotor, circadian rhythmic activity, and anxiety-like behavior. Hippocampal cell proliferation as well as hippocampal and frontal cortex BDNF levels was not affected by music across aging. Cognitive improvement by music in aging rats may require distinct neurobiological mechanisms than hippocampal cell proliferation and BDNF.
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Affiliation(s)
- Lou Rizzolo
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
| | - Marianne Leger
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
| | - Sophie Corvaisier
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
| | - Mathilde Groussard
- Normandie University, Unicaen, PSL Research University, EPHE, INSERM U1077, CHU de Caen, Cyceron, 14000 Caen, France
- PSL Research University, EPHE, Paris, France
| | - Hervé Platel
- Normandie University, Unicaen, PSL Research University, EPHE, INSERM U1077, CHU de Caen, Cyceron, 14000 Caen, France
- PSL Research University, EPHE, Paris, France
| | - Valentine Bouet
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
| | - Pascale Schumann-Bard
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
| | - Thomas Freret
- Normandie University, Unicaen, INSERM, COMETE, CHU de Caen, Cyceron, 14000 Caen, France
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Sbrini G, Brivio P, Bosch K, Homberg JR, Calabrese F. Enrichment Environment Positively Influences Depression- and Anxiety-Like Behavior in Serotonin Transporter Knockout Rats through the Modulation of Neuroplasticity, Spine, and GABAergic Markers. Genes (Basel) 2020; 11:genes11111248. [PMID: 33114023 PMCID: PMC7690660 DOI: 10.3390/genes11111248] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 02/06/2023] Open
Abstract
The serotonin transporter (5-HTT in humans, SERT in rodents) is the main regulator of serotonergic transmission in the brain. The short allelic variant of the 5-HTT gene is in humans associated with psychopathologies and may enhance the vulnerability to develop depression after exposure to stressful events. Interestingly, the short allele also increases the sensitivity to a positive environment, which may buffer the vulnerability to depression. Since this polymorphism does not exist in rodents, male SERT knockout (SERT−/−) rats were tested to explore the molecular mechanisms based on this increased predisposition. This article investigates the influences of a positive manipulation, namely, enriched environment (EE), on the depressive-like behavior observed in SERT−/− rats. We found that one month of EE exposure normalized the anhedonic and anxious-like phenotype characteristics of this animal model. Moreover, we observed that EE exposure also restored the molecular alterations in the prefrontal cortex by positively modulating the expression of the neurotrophin Bdnf, and of spines and gamma-aminobutyric acid (GABA)ergic markers. Overall, our data confirm the depression-like phenotype of SERT−/− rats and highlight the ability of EE to restore behavioral and molecular alterations, thus promoting the opportunity to use EE as a supporting non-pharmacological approach to treat mood disorders.
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Affiliation(s)
- Giulia Sbrini
- Department of Pharmacological and Biomolecular Sciences, Università Degli Studi di Milano, 20133 Milan, Italy; (G.S.); (P.B.)
| | - Paola Brivio
- Department of Pharmacological and Biomolecular Sciences, Università Degli Studi di Milano, 20133 Milan, Italy; (G.S.); (P.B.)
| | - Kari Bosch
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands; (K.B.); (J.R.H.)
| | - Judith Regina Homberg
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands; (K.B.); (J.R.H.)
| | - Francesca Calabrese
- Department of Pharmacological and Biomolecular Sciences, Università Degli Studi di Milano, 20133 Milan, Italy; (G.S.); (P.B.)
- Correspondence: ; Tel.: +02-50318277
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35
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Stevenson W, Hase Y, Wilson E, Hollins A, Hase M, Ennaceur A, Craggs L, Ihara M, Horsburgh K, Kalaria RN. Long-term effects of experimental carotid stenosis on hippocampal infarct pathology, neurons and glia and amelioration by environmental enrichment. Brain Res Bull 2020; 163:72-83. [PMID: 32707262 DOI: 10.1016/j.brainresbull.2020.07.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/03/2020] [Accepted: 07/15/2020] [Indexed: 01/17/2023]
Abstract
Hippocampal atrophy and pathology are common in ageing-related disorders and associated with cognitive impairment and dementia. We explored whether environmental enrichment (EE) ameliorated the pathological sequelae in the hippocampus subsequent to chronic cerebral hypoperfusion induced by bilateral common carotid artery stenosis (BCAS). Seventy-four male C57BL/6 J mice underwent BCAS or sham surgery. One-week after surgery, mice were exposed to three different degrees of EE; either standard housing conditions (std), limited 3 -h exposure to EE per day (3 h) or full-time exposure to EE (full) for 3 months. Four months after surgery, the hippocampus was examined for the extent of vascular brain injury and neuronal and glial changes. Results showed that long-term BCAS induced strokes, most often in CA1 subfield, reduced 40-50 % CA1 neurons (P < 0.01) and increased microglia/macrophage in CA1-CA3 subfields (P < 0.02). Remarkably, both 3 h and full-time EE regimes attenuated hippocampal neuronal death and repressed recurrent strokes with complete prevention of larger infarcts in mice on full-time EE (P < 0.01). Full-time EE also reduced astrocytic clasmatodendrosis and microglial/macrophage activation in all CA subfields. Our results suggest that exposure to EE differentially reduces long-term hypoperfusive hippocampal damage. The implementation of even limited EE may be beneficial for patients diagnosed with vascular cognitive impairment.
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Affiliation(s)
- William Stevenson
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Yoshiki Hase
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Elle Wilson
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Annabel Hollins
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Mai Hase
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Abdel Ennaceur
- Department of Pharmacy, Sunderland Pharmacy School, The University of Sunderland, Sunderland, UK
| | - Lucy Craggs
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Masafumi Ihara
- Department of Neurology, National Cerebral and Cardiovascular Centre, Osaka, Japan
| | - Karen Horsburgh
- Centre for Discovery Brain Sciences, The University of Edinburgh, Edinburgh, UK
| | - Raj N Kalaria
- Neurovascular Research Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK.
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36
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Wu YF, Zhang YM, Ge HH, Ren CY, Zhang ZZ, Cao L, Wang F, Chen GH. Effects of Embryonic Inflammation and Adolescent Psychosocial Environment on Cognition and Hippocampal Staufen in Middle-Aged Mice. Front Aging Neurosci 2020; 12:578719. [PMID: 33024434 PMCID: PMC7516039 DOI: 10.3389/fnagi.2020.578719] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 08/24/2020] [Indexed: 12/21/2022] Open
Abstract
Accumulating evidence has indicated that embryonic inflammation could accelerate age-associated cognitive impairment, which can be attributed to dysregulation of synaptic plasticity-associated proteins, such as RNA-binding proteins (RBPs). Staufen is a double-stranded RBP that plays a critical role in the modulation of synaptic plasticity and memory. However, relatively few studies have investigated how embryonic inflammation affects cognition and neurobiology during aging, or how the adolescent psychosocial environment affects inflammation-induced remote cognitive impairment. Consequently, the aim of this study was to investigate whether these adverse factors can induce changes in Staufen expression, and whether these changes are correlated with cognitive impairment. In our study, CD-1 mice were administered lipopolysaccharides (LPS, 50 μg/kg) or an equal amount of saline (control) intraperitoneally during days 15–17 of gestation. At 2 months of age, male offspring were randomly exposed to stress (S), an enriched environment (E), or not treated (CON) and then assigned to five groups: LPS, LPS+S, LPS+E, CON, and CON+S. Mice were evaluated at 3-month-old (young) and 15-month-old (middle-aged). Cognitive function was assessed using the Morris water maze test, while Staufen expression was examined at both the protein and mRNA level using immunohistochemistry/western blotting and RNAscope technology, respectively. The results showed that the middle-aged mice had worse cognitive performance and higher Staufen expression than young mice. Embryonic inflammation induced cognitive impairment and increased Staufen expression in the middle-aged mice, whereas adolescent stress/an enriched environment would accelerated/mitigated these effects. Meanwhile, Staufen expression was closely correlated with cognitive performance. Our findings suggested embryonic inflammation can accelerate age-associated learning and memory impairments, and these effects may be related to the Staufen expression.
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Affiliation(s)
- Yong-Fang Wu
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Yue-Ming Zhang
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - He-Hua Ge
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Chong-Yang Ren
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Zhe-Zhe Zhang
- Department of Neurology and Critical Care, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Lei Cao
- Department of Neurology, The Second Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Fang Wang
- Department of Neurology and Critical Care, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Gui-Hai Chen
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
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Clemenson GD, Stark SM, Rutledge SM, Stark CEL. Enriching hippocampal memory function in older adults through video games. Behav Brain Res 2020; 390:112667. [PMID: 32439346 PMCID: PMC7286064 DOI: 10.1016/j.bbr.2020.112667] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/21/2020] [Accepted: 04/21/2020] [Indexed: 01/17/2023]
Abstract
Healthy aging is accompanied by a steady cognitive decline with clear losses in memory. Animal studies have consistently demonstrated that simply modifying an animal's living environment (known as environmental enrichment) can have a positive influence on age-related cognitive decline in the hippocampus. Previously, we showed that playing immersive 3D video games can improve hippocampal-based memory in young healthy adults, suggesting that the exploration of the large open worlds of modern-day video games may act as proxy for environmental enrichment in humans. Here, we replicated our previous video game study in healthy older adults, showing that playing video games for four weeks can improve hippocampal-based memory in a population that is already experiencing age-related decline in memory. Furthermore, we showed that the improvements last for up to four weeks past the intervention, highlighting the potential of video games as intervention for age-related cognitive decline.
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Affiliation(s)
- Gregory D Clemenson
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, 92697, United States
| | - Shauna M Stark
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, 92697, United States
| | - Samantha M Rutledge
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, 92697, United States
| | - Craig E L Stark
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, 92697, United States.
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Prabhu GS, K G Rao M, Rai KS. Hippocampal neural cell degeneration and memory deficit in high-fat diet-induced postnatal obese rats- exploring the comparable benefits of choline and DHA or environmental enrichment. Int J Neurosci 2020; 131:1066-1077. [PMID: 32498586 DOI: 10.1080/00207454.2020.1773819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Purpose: Childhood obesity increases risk for neural dysfunctions causing learning and memory deficits. The objective of the study is to identify the effects of high fat diet-induced obesity in postnatal period on serum lipids, memory and neural cell survival in hippocampus and compare the role of choline and DHA or environmental enrichment in attenuating the alterationsMaterials and methods: 21 day postnatal male Sprague Dawley rats were assigned as Normal control [NC] fed normal chow diet, Obesity-induced [OB] fed high fat diet, Obesity-induced fed choline & DHA [OB + CHO + DHA], Obesity-induced environmental enrichment [OB + EE] [n = 8/group]. Memory was assessed using radial arm maze. Subsequently blood was collected for serum lipid analysis and rats were euthanized. 5 µm hippocampal sections were processed for cresyl-violet stain. Surviving neural cells were counted using 100 µm scale.Results: Memory errors were significantly higher [p < 0.001, 0.01] in OB compared to same in NC rats. Mean number of surviving neural cells in hippocampus of OB was significantly lesser [p < 0.01] compared to same in NC. Interventions in OB + CHO + DHA and OB + EE significantly attenuated [p < 0.01] memory errors and number of surviving neural cells in hippocampus [CA1, CA3 and DG] compared to same in OB. Moreover, hippocampal neural cell survival was found to be inversely related to serum lipid profile in OB group and was attenuated in OB + CHO + DHA and OB + EE rats.Conclusions: High fat diet-induced postnatal obesity in rats causes CA1/CA3 hippocampal neuro-degeneration and memory deficits. Supplementation of choline and DHA in obese rats attenuates these deficits.
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Affiliation(s)
- Gayathri S Prabhu
- Department of Anatomy, Melaka Manipal Medical College [Manipal campus], Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Mohandas K G Rao
- Department of Anatomy, Melaka Manipal Medical College [Manipal campus], Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Kiranmai S Rai
- Department of Physiology, Melaka Manipal Medical College [Manipal campus], Manipal Academy of Higher Education, Manipal, Karnataka, India
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Liu WC, Wu CW, Hung PL, Chan JYH, Tain YL, Fu MH, Chen LW, Liang CK, Hung CY, Yu HR, Chen IC, Wu KL. Environmental Stimulation Counteracts the Suppressive Effects of Maternal High-Fructose Diet on Cell Proliferation and Neuronal Differentiation in the Dentate Gyrus of Adult Female Offspring via Histone Deacetylase 4. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17113919. [PMID: 32492926 PMCID: PMC7312637 DOI: 10.3390/ijerph17113919] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/23/2020] [Accepted: 05/29/2020] [Indexed: 12/27/2022]
Abstract
Maternal high-fructose diets (HFD) impair the learning and memory capacity of adult female offspring via histone deacetylase 4 (HDAC4). Hippocampal adult neurogenesis is important for supporting the function of existing neural circuits. In this study, we investigated the effects of maternal HFD on hippocampal neural stem cell (NSC) proliferation and neuronal differentiation in adult offspring. Increased nuclear HDAC4 enzyme activity was detected in the hippocampus of HFD female offspring. The Western blot analyses indicated that the expressions of sex-determining region Y box2 (SOX2) and the transcription factor Paired Box 6 (PAX6), which are critical for the progression of NSC proliferation and differentiation, were downregulated. Concurrently, the expression of Ki67 (a cellular marker for proliferation) and doublecortin (DCX), which are related to NSC division and neuronal differentiation, was suppressed. Intracerebroventricular infusion with class II HDAC inhibitor (Mc1568, 4 weeks) led to the upregulation of these proteins. Environmental stimulation reversed the expression of Ki67 and DCX and the counts of Ki67- and DCX-positive cells in the hippocampi of HFD offspring as a result of providing the enriched housing for 4 weeks. Together, these results demonstrate that the suppressive effects of maternal HFD on hippocampal NSC proliferation and neuronal differentiation are reversibly mediated through HDAC4 and can be effectively reversed by environmental stimulation. The advantageous effects of environmental enrichment were possibly mediated by HDAC4 suppression.
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Affiliation(s)
- Wen-Chung Liu
- Division of Plastic and Reconstructive Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan; (W.-C.L.); (L.-W.C.)
- Department of Surgery, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan
| | - Chih-Wei Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
- National Kaohsiung University of Science and Technology, Kaohsiung 83301, Taiwan
| | - Pi-Lien Hung
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (P.-L.H.); (H.-R.Y.)
| | - Julie Y. H. Chan
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
| | - You-Lin Tain
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (P.-L.H.); (H.-R.Y.)
- College of Medicine, Chang Gung University, Kaohsiung 83301, Taiwan
| | - Mu-Hui Fu
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan;
| | - Lee-Wei Chen
- Division of Plastic and Reconstructive Surgery, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan; (W.-C.L.); (L.-W.C.)
| | - Chih-Kuang Liang
- Center for Geriatrics and Gerontology and Division of Neurology, Kaohsiung Veterans General Hospital, Kaohsiung 81362, Taiwan;
| | - Chun-Ying Hung
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
| | - Hong-Ren Yu
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (P.-L.H.); (H.-R.Y.)
| | - I-Chun Chen
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
| | - Kay L.H. Wu
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan; (C.-W.W.); (J.Y.H.C.); (Y.-L.T.); (C.-Y.H.); (I.-C.C.)
- Department of Senior Citizen Services, National Tainan Institute of Nursing, Tainan 700, Taiwan
- Correspondence:
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Tripathi S, Verma A, Jha SK. Training on an Appetitive Trace-Conditioning Task Increases Adult Hippocampal Neurogenesis and the Expression of Arc, Erk and CREB Proteins in the Dorsal Hippocampus. Front Cell Neurosci 2020; 14:89. [PMID: 32362814 PMCID: PMC7181388 DOI: 10.3389/fncel.2020.00089] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 03/26/2020] [Indexed: 12/11/2022] Open
Abstract
Adult hippocampal neurogenesis (AHN) plays an essential role in hippocampal-dependent memory consolidation. Increased neurogenesis enhances learning, whereas its ablation causes memory impairment. In contrast, few reports suggest that neurogenesis reduces after learning. Although the interest in exploring the role of adult neurogenesis in learning has been growing, the evidence is still limited. The role of the trace- and delay-appetitive-conditioning on AHN and its underlying mechanism are not known. The consolidation of trace-conditioned memory requires the hippocampus, but delay-conditioning does not. Moreover, the dorsal hippocampus (DH) and ventral hippocampus (VH) may have a differential role in these two conditioning paradigms. Here, we have investigated the changes in: (A) hippocampal cell proliferation and their progression towards neuronal lineage; and (B) expression of Arc, Erk1, Erk2, and CREB proteins in the DH and VH after trace- and delay-conditioning in the rat. The number of newly generated cells significantly increased in the trace-conditioned but did not change in the delay-conditioned animals compared to the control group. Similarly, the expression of Arc protein significantly increased in the DH but not in the VH after trace-conditioning. Nonetheless, it remains unaltered in the delay-conditioned group. The expression of pErk1, pErk2, and pCREB also increased in the DH after trace-conditioning. Whereas, the expression of only pErk1 pErk2 and pCREB proteins increased in the VH after delay-conditioning. Our results suggest that appetitive trace-conditioning enhances AHN. The increased DH neuronal activation and pErk1, pErk2, and pCREB in the DH may be playing an essential role in learning-induced cell-proliferation after appetitive trace-conditioning.
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Affiliation(s)
- Shweta Tripathi
- School of Life Science, Jawaharlal Nehru University, New Delhi, India
| | - Anita Verma
- School of Life Science, Jawaharlal Nehru University, New Delhi, India
| | - Sushil K Jha
- School of Life Science, Jawaharlal Nehru University, New Delhi, India
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Pretsch G, Sanadgol N, Smidak R, Lubec J, Korz V, Höger H, Zappe K, Cichna‑Markl M, Lubec G. Doublecortin and IGF-1R protein levels are reduced in spite of unchanged DNA methylation in the hippocampus of aged rats. Amino Acids 2020; 52:543-553. [DOI: 10.1007/s00726-020-02834-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 03/04/2020] [Indexed: 11/24/2022]
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Man J, Cui K, Fu X, Zhang D, Lu Z, Gao Y, Yu L, Li N, Wang J. Donepezil promotes neurogenesis via Src signaling pathway in a rat model of chronic cerebral hypoperfusion. Brain Res 2020; 1736:146782. [PMID: 32184165 DOI: 10.1016/j.brainres.2020.146782] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 02/15/2020] [Accepted: 03/12/2020] [Indexed: 01/23/2023]
Abstract
Donepezil, a selective acetylcholinesterase (AchE) inhibitor, enhances stroke-induced neurogenesis within subventricular zone (SVZ). Src/Pyk-2 is one of the downstream pathways of acetylcholine receptors (AchRs), and has been shown to participate in the activation of fibroblast growth factor receptor (FGFR)/epidermal growth factor receptor (EGFR) signaling in cancer cells. In this study, we investigated whether donepezil could promote SVZ neurogenesis in chronic cerebral hypoperfusion (CCH) injury via Src signaling pathway. In the bilateral carotid artery occlusion (2VO) rat model, we observed more nestin/5-bromo-2'-deoxyuridine (BrdU)-positive cells and doublecortin (DCX)/BrdU-positive cells in the SVZ than that in the sham group. Further, donepezil obviously improved neurologic function after 2VO, induced the greater number of SVZ proliferative NSCs and neuroblasts, and elevated levels of Src, p-FGFR1, p-EGFR, p-Akt and p-Raf in ipsilateral SVZ. Lastly, Src inhibitor KX-01 abolished the beneficial effects of donepezil in 2VO rats. These results suggest that donepezil could upregulate Src signaling pathway to enhance CCH-induced SVZ neurogenesis.
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Affiliation(s)
- Jiang Man
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Kefei Cui
- Department of Ultrasound, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Xiaojie Fu
- Department of Neurointervention, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Di Zhang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Zhengfang Lu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Yufeng Gao
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Lie Yu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Nan Li
- Department of Neurology, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Jianping Wang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
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Blok J, Black DA, Petersen J, Sawatari A, Leamey CA. Environmental Enrichment Rescues Visually-Mediated Behavior in Ten-m3 Knockout Mice During an Early Critical Period. Front Behav Neurosci 2020; 14:22. [PMID: 32158383 PMCID: PMC7052109 DOI: 10.3389/fnbeh.2020.00022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 01/31/2020] [Indexed: 11/13/2022] Open
Abstract
Environmental enrichment (EE) has been shown to promote neural plasticity. Its capacity to induce functional repair in models which exhibit profound sensory deficits due to aberrant axonal guidance has not been well-characterized. Ten-m3 knockout (KO) mice exhibit a highly-stereotyped miswiring of ipsilateral retinogeniculate axons and associated profound deficits in binocularly-mediated visual behavior. We determined whether, and when, EE can drive functional recovery by analyzing Ten-m3 KO and wildtype (WT) mice that were enriched for 6 weeks from adulthood, weaning or birth in comparison to standard-housed controls. EE initiated from birth, but not later, rescued the response of Ten-m3 KOs to the "looming" stimulus (expanding disc in dorsal visual field), suggesting improved visual function. EE can thus induce recovery of visual behavior, but only during an early developmentally-restricted time-window.
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Affiliation(s)
- James Blok
- Department of Physiology, School of Medical Sciences and Bosch Institute, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
| | - Dylan A Black
- Department of Physiology, School of Medical Sciences and Bosch Institute, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
| | - Justin Petersen
- Department of Physiology, School of Medical Sciences and Bosch Institute, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
| | - Atomu Sawatari
- Department of Physiology, School of Medical Sciences and Bosch Institute, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
| | - Catherine A Leamey
- Department of Physiology, School of Medical Sciences and Bosch Institute, Faculty of Medicine and Health, University of Sydney, Camperdown, NSW, Australia
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What Do Microglia Really Do in Healthy Adult Brain? Cells 2019; 8:cells8101293. [PMID: 31652490 PMCID: PMC6829860 DOI: 10.3390/cells8101293] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/17/2019] [Accepted: 10/18/2019] [Indexed: 12/27/2022] Open
Abstract
Microglia originate from yolk sac-primitive macrophages and auto-proliferate into adulthood without replacement by bone marrow-derived circulating cells. In inflammation, stroke, aging, or infection, microglia have been shown to contribute to brain pathology in both deleterious and beneficial ways, which have been studied extensively. However, less is known about their role in the healthy adult brain. Astrocytes and oligodendrocytes are widely accepted to strongly contribute to the maintenance of brain homeostasis and to modulate neuronal function. On the other hand, contribution of microglia to cognition and behavior is only beginning to be understood. The ability to probe their function has become possible using microglial depletion assays and conditional mutants. Studies have shown that the absence of microglia results in cognitive and learning deficits in rodents during development, but this effect is less pronounced in adults. However, evidence suggests that microglia play a role in cognition and learning in adulthood and, at a cellular level, may modulate adult neurogenesis. This review presents the case for repositioning microglia as key contributors to the maintenance of homeostasis and cognitive processes in the healthy adult brain, in addition to their classical role as sentinels coordinating the neuroinflammatory response to tissue damage and disease.
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Neurodegeneration and Neuro-Regeneration-Alzheimer's Disease and Stem Cell Therapy. Int J Mol Sci 2019; 20:ijms20174272. [PMID: 31480448 PMCID: PMC6747457 DOI: 10.3390/ijms20174272] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 12/17/2022] Open
Abstract
Aging causes many changes in the human body, and is a high risk for various diseases. Dementia, a common age-related disease, is a clinical disorder triggered by neurodegeneration. Brain damage caused by neuronal death leads to cognitive decline, memory loss, learning inabilities and mood changes. Numerous disease conditions may cause dementia; however, the most common one is Alzheimer’s disease (AD), a futile and yet untreatable illness. Adult neurogenesis carries the potential of brain self-repair by an endogenous formation of newly-born neurons in the adult brain; however it also declines with age. Strategies to improve the symptoms of aging and age-related diseases have included different means to stimulate neurogenesis, both pharmacologically and naturally. Finally, the regulatory mechanisms of stem cells neurogenesis or a functional integration of newborn neurons have been explored to provide the basis for grafted stem cell therapy. This review aims to provide an overview of AD pathology of different neural and glial cell types and summarizes current strategies of experimental stem cell treatments and their putative future use in clinical settings.
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Voglewede RL, Vandemark KM, Davidson AM, DeWitt AR, Heffler MD, Trimmer EH, Mostany R. Reduced sensory-evoked structural plasticity in the aging barrel cortex. Neurobiol Aging 2019; 81:222-233. [PMID: 31323444 DOI: 10.1016/j.neurobiolaging.2019.06.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 06/15/2019] [Accepted: 06/15/2019] [Indexed: 10/26/2022]
Abstract
Impairments in synaptic connectivity have been linked to cognitive deficits in age-related neurodegenerative disorders and healthy aging. However, the anatomical and structural bases of these impairments have not been identified yet. A hallmark of neural plasticity in young adults is short-term synaptic rearrangement, yet aged animals already display higher synaptic turnover rates at the baseline. Using two-photon excitation (2PE) microscopy, we explored if this elevated turnover alters the aged brain's response to plasticity. Following a sensory-evoked plasticity protocol involving whisker stimulation, aged mice display reduced spine dynamics (gain, loss, and turnover), decreased spine clustering, and lower spine stability when compared to young adult mice. These results suggest a deficiency of the cortical neurons of aged mice to structurally incorporate new sensory experiences, in the form of clustered, long-lasting synapses, into already existing cortical circuits. This research provides the first evidence linking experience-dependent plasticity with in vivo spine dynamics in the aged brain and supports a model of both reduced synaptic plasticity and reduced synaptic tenacity in the aged somatosensory system.
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Affiliation(s)
- Rebecca L Voglewede
- Neuroscience Program, Tulane University School of Science and Engineering, New Orleans, LA, USA; Tulane Brain Institute, Tulane University, New Orleans, LA, USA; Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Kaeli M Vandemark
- Neuroscience Program, Tulane University School of Science and Engineering, New Orleans, LA, USA; Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Andrew M Davidson
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA; Department of Cell and Molecular Biology, Tulane University School of Science and Engineering, New Orleans, LA, USA
| | - Annie R DeWitt
- Neuroscience Program, Tulane University School of Science and Engineering, New Orleans, LA, USA; Tulane Brain Institute, Tulane University, New Orleans, LA, USA
| | - Marissa D Heffler
- Neuroscience Program, Tulane University School of Science and Engineering, New Orleans, LA, USA; Tulane Brain Institute, Tulane University, New Orleans, LA, USA; Department of Biomedical Engineering, Tulane University School of Science and Engineering, Lindy Boggs Center Suite 500, New Orleans, LA, USA
| | - Emma H Trimmer
- Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Ricardo Mostany
- Neuroscience Program, Tulane University School of Science and Engineering, New Orleans, LA, USA; Tulane Brain Institute, Tulane University, New Orleans, LA, USA; Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA.
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Biggio F, Mostallino M, Talani G, Locci V, Mostallino R, Calandra G, Sanna E, Biggio G. Social enrichment reverses the isolation-induced deficits of neuronal plasticity in the hippocampus of male rats. Neuropharmacology 2019; 151:45-54. [DOI: 10.1016/j.neuropharm.2019.03.030] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 03/21/2019] [Accepted: 03/26/2019] [Indexed: 02/07/2023]
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Thamizhoviya G, Vanisree AJ. Enriched environment modulates behavior, myelination and augments molecules governing the plasticity in the forebrain region of rats exposed to chronic immobilization stress. Metab Brain Dis 2019; 34:875-887. [PMID: 30604029 DOI: 10.1007/s11011-018-0370-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 12/11/2018] [Indexed: 01/10/2023]
Abstract
Recently, several reports on chronic stress have shown that prolonged exposure to stress contributes to psychological and neurological complications. However, the impact of stress-induced alterations in myelination remains to be unexplored. Therefore, in the current study, the rats were subjected to immobilization stress (IS) followed by enriched environment (EE) and the behavioral, neurochemical changes pertaining to neuronal survival pathway, in addition, to the ultrastructural changes in myelin in forebrain (FB) region of rats were analyzed. Immobilization stress-exposed rats (4 h/day IS, for 28 days) exhibited increased anhedonia, anxiety, immobility, and reduced social interaction, which could be reflected in increased levels of corticosterone. In contrast, exposure to EE (4 h IS+2 h EE/day, for 28 days) was found to minimize anhedonic state, supress the depressive-like features, enhance social interaction and also reduce the levels of corticosterone. The ultrastructural changes in the FB region of the brain revealed that IS group showed enhanced g-ratio indicating decreased myelin thickness, while EE group exhibited reduced g-ratio manifesting increased myelination. Further, the study revealed that IS exposed group showed decreased levels of NGF, TrkA, PI3K, AKT, ERK, CREB, and MBP in FB regions whereas EE group could preserve normal protein and mRNA levels of these neuronal survival molecules. The results from this study suggest that EE exerts a positive impact by improving myelination in rats exposed to chronic immobilization stress.
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Moreno-Jiménez EP, Jurado-Arjona J, Ávila J, Llorens-Martín M. The Social Component of Environmental Enrichment Is a Pro-neurogenic Stimulus in Adult c57BL6 Female Mice. Front Cell Dev Biol 2019; 7:62. [PMID: 31080799 PMCID: PMC6497743 DOI: 10.3389/fcell.2019.00062] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 04/05/2019] [Indexed: 12/18/2022] Open
Abstract
In rodents, the hippocampal dentate gyrus gives rise to newly generated dentate granule cells (DGCs) throughout life. This process, named adult hippocampal neurogenesis (AHN), converges in the functional integration of mature DGCs into the trisynaptic hippocampal circuit. Environmental enrichment (EE) is one of the most potent positive regulators of AHN. This paradigm includes the combination of three major stimulatory components, namely increased physical activity, constant cognitive stimulation, and higher social interaction. In this regard, the pro-neurogenic effects of physical activity and cognitive stimulation have been widely addressed in adult rodents. However, the pro-neurogenic potential of the social aspect of EE has been less explored to date. Here we tackled this question by specifically focusing on the effects of a prolonged period of social enrichment (SE) in adult female C57BL6 mice. To this end, 7-week-old mice were housed in groups of 12 per cage for 8 weeks. These mice were compared with others housed under control housing (2–3 mice per cage) or EE (12 mice per cage plus running wheels and toys) conditions during the same period. We analyzed the number and morphology of Doublecortin-expressing (DCX+) cells. Moreover, using RGB retroviruses that allowed the labeling of three populations of newborn DGCs of different ages in the same mouse, we performed morphometric, immunohistochemical, and behavioral determinations. Both SE and EE increased the number and maturation of DCX+ cells, and caused an increase in dendritic maturation in certain populations of newborn DGCs. Moreover, both manipulations increased exploratory behavior in the Social Interaction test. Unexpectedly, our data revealed the potent neurogenesis-stimulating potential of SE in the absence of any further cognitive stimulation or increase in physical activity. Given that an increase in physical activity is strongly discouraged under certain circumstances, our findings may be relevant in the context of enhancing AHN via physical activity-independent mechanisms.
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Affiliation(s)
- Elena P Moreno-Jiménez
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa, CBMSO, CSIC-UAM, Madrid, Spain.,Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain.,Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - Jerónimo Jurado-Arjona
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa, CBMSO, CSIC-UAM, Madrid, Spain
| | - Jesús Ávila
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa, CBMSO, CSIC-UAM, Madrid, Spain.,Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - María Llorens-Martín
- Department of Molecular Neuropathology, Centro de Biología Molecular Severo Ochoa, CBMSO, CSIC-UAM, Madrid, Spain.,Department of Molecular Biology, Faculty of Sciences, Universidad Autónoma de Madrid, Madrid, Spain.,Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Madrid, Spain
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Aged rats with different performances at environmental enrichment onset display different modulation of habituation and aversive memory. Neurobiol Learn Mem 2019; 161:83-91. [PMID: 30951838 DOI: 10.1016/j.nlm.2019.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/20/2019] [Accepted: 04/01/2019] [Indexed: 12/22/2022]
Abstract
A wide agreement exists that environmental enrichment (EE) is most beneficial if introduced early in life, but numerous studies reported that also aged animals remain responsive. As age-related memory and cognition impairments are not uniform, an open question is whether EE might exert different effects in animals with different age-related deficits. A 12-week EE protocol was applied to late adult rats pretested for habituation and aversive memory. Animals were classified as low (LP) and high (HP) performers according to percent exploration change in Open Field test (OF) and as impaired (I) and not impaired (NI) according to latency in Step-through Passive Avoidance test (PA). Standard housing (SH) animals pretested by OF and PA, and naïve (non-pretested) EE and SH rats were used as controls. In comparison to pretest, after the housing protocol, EE LP ameliorated while EE HP and both SH HP and LP worsened their habituation pattern. The positive influence of EE on LP was probably due to the more active interaction with and the faster adaptation to surroundings promoted by continuous, multiple stimuli provided during the enriched housing. Regarding HP, EE did not boost the basal behavior, which likely represented the maximum achievable for that age, and the post housing exploration change dropped, as in SH animals, because of the retesting. After EE, a significant percentage of NI animals became I and a significant percentage of I animals became NI. The changes evidenced in the NI group likely depended on EE-related reduction of anxiety and the consequent more efficient coping with fearful situations. This hypothesis was strengthened by the observation that naïve EE animals were almost all I. Pretested EE I rats were not influenced by the rearing condition: their behavior was comparable to SH animals' behavior and determined by retesting. In conclusion, these results demonstrated that, when applied to aging rats, EE produces different effects based on pre-housing cognitive performances. The issue needs further analyses, but the observation that not all animals are able to take advantage of EE to the same extent suggests the opportunity to design individually tailored approaches to optimize their efficacy and minimize possible unwanted consequences.
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