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da Silva RPB, Pinheiro IL, da Silva RKB, Moretti EC, de Oliveira Neto OB, Ferraz-Pereira K, Galindo LCM. Social isolation and post-weaning environmental enrichment effects on rat emotional behavior and serotonergic system. Int J Dev Neurosci 2024; 84:265-280. [PMID: 38526313 DOI: 10.1002/jdn.10324] [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: 10/08/2023] [Revised: 01/29/2024] [Accepted: 02/20/2024] [Indexed: 03/26/2024] Open
Abstract
Social isolation (SI) is related to adverse neurobehavioral effects and neurochemical changes when it occurs early in development. On the other hand, environmental enrichment (EE) is associated with a reduction in anxiety-like and depression-like behavior, as well as an increase in serotonin (5-HT) levels in the prefrontal cortex and hippocampus in rodents. This study systematically reviewed the effects of SI and EE on emotional behavior and serotonergic system components in rats after weaning. Primary experimental studies that used subgroups of rats subjected to SI, EE, and normal social conditions after weaning were considered eligible. Studies that used transgenic rodents, ex vivo studies, in vitro studies, human research, or in silico studies were ineligible. Two authors completed searches in Medline/PubMed, LILACS, Scopus, Web of Science, EMBASE, and Open Gray. The Kappa index was calculated to assess agreement between reviewers and assess study quality. The results showed that the animals exposed to EE showed better adaptation to a new environment. Furthermore, EE increased 5-HT levels in the hippocampus and prefrontal cortex of rodents. Thus, it appears that an EE during the critical period of development may reduce anxiety/depression-like behaviors, as well as increase long-term neurotransmitter response.
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Affiliation(s)
- Roxana Patrícia Bezerra da Silva
- Post-Graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Pernambuco, Vitória de Santo Antão, Brazil
| | - Isabeli Lins Pinheiro
- Post-Graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Pernambuco, Vitória de Santo Antão, Brazil
- Nutrition and Phenotypic Plasticity Study Unit, Department of Nutrition, Federal University of Pernambuco, Recife, Brazil
| | - Regina Katiuska Bezerra da Silva
- Post-Graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Pernambuco, Vitória de Santo Antão, Brazil
| | | | | | - Kelli Ferraz-Pereira
- Nutrition and Phenotypic Plasticity Study Unit, Department of Nutrition, Federal University of Pernambuco, Recife, Brazil
- Department Speech Therapy, Federal University of Pernambuco, Recife, Brazil
| | - Lígia Cristina Monteiro Galindo
- Post-Graduate Program in Nutrition, Physical Activity and Phenotypic Plasticity, Federal University of Pernambuco, Vitória de Santo Antão, Brazil
- Nutrition and Phenotypic Plasticity Study Unit, Department of Nutrition, Federal University of Pernambuco, Recife, Brazil
- Department of Anatomy, Federal University of Pernambuco, Recife, Brazil
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Caine S, Alaverdashvili M, Colbourne F, Muir GD, Paterson PG. A modified rehabilitation paradigm bilaterally increased rat extensor digitorum communis muscle size but did not improve forelimb function after stroke. PLoS One 2024; 19:e0302008. [PMID: 38603768 PMCID: PMC11008896 DOI: 10.1371/journal.pone.0302008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 03/26/2024] [Indexed: 04/13/2024] Open
Abstract
Malnutrition after stroke may lessen the beneficial effects of rehabilitation on motor recovery through influences on both brain and skeletal muscle. Enriched rehabilitation (ER), a combination of environmental enrichment and forelimb reaching practice, is used preclinically to study recovery of skilled reaching after stroke. However, the chronic food restriction typically used to motivate engagement in reaching practice is a barrier to using ER to investigate interactions between nutritional status and rehabilitation. Thus, our objectives were to determine if a modified ER program comprised of environmental enrichment and skilled reaching practice motivated by a short fast would enhance post-stroke forelimb motor recovery and preserve forelimb muscle size and metabolic fiber type, relative to a group exposed to stroke without ER. At one week after photothrombotic cortical stroke, male, Sprague-Dawley rats were assigned to modified ER or standard care for 2 weeks. Forelimb recovery was assessed in the Montoya staircase and cylinder task before stroke and on days 5-6, 22-23, and 33-34 after stroke. ER failed to improve forelimb function in either task (p > 0.05). Atrophy of extensor digitorum communis (EDC) and triceps brachii long head (TBL) muscles was not evident in the stroke-targeted forelimb on day 35, but the area occupied by hybrid fibers was increased in the EDC muscle (p = 0.038). ER bilaterally increased EDC (p = 0.046), but not TBL, muscle size; EDC muscle fiber type was unchanged by ER. While the modified ER did not promote forelimb motor recovery, it does appear to have utility for studying the role of skeletal muscle plasticity in post-stroke recovery.
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Affiliation(s)
- Sally Caine
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada
| | | | - Frederick Colbourne
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
- Department of Psychology, University of Alberta, Edmonton, Canada
| | - Gillian D. Muir
- Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Phyllis G. Paterson
- College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada
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Harris BN, Yavari M, Ramalingam L, Mounce PL, Alers Maldonado K, Chavira AC, Thomas S, Scoggin S, Biltz C, Moustaid-Moussa N. Impact of Long-Term Dietary High Fat and Eicosapentaenoic Acid on Behavior and Hypothalamic-Pituitary-Adrenal Axis Activity in Amyloidogenic APPswe/PSEN1dE9 Mice. Neuroendocrinology 2024; 114:553-576. [PMID: 38301617 PMCID: PMC11153005 DOI: 10.1159/000536586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 01/30/2024] [Indexed: 02/03/2024]
Abstract
INTRODUCTION Alzheimer's disease (AD) alters neurocognitive and emotional function and causes dysregulation of multiple homeostatic processes. The leading AD framework pins amyloid beta plaques and tau tangles as primary drivers of dysfunction. However, many additional variables, including diet, stress, sex, age, and pain tolerance, interact in ways that are not fully understood to impact the onset and progression of AD pathophysiology. We asked: (1) does high-fat diet, compared to low-fat diet, exacerbate AD pathophysiology and behavioral decline? And, (2) can supplementation with eicosapentaenoic (EPA)-enriched fish oil prevent high-fat-diet-induced changes? METHODS Male and female APPswePSdE9 mice, and their non-transgenic littermates, were randomly assigned to a diet condition (low-fat, high-fat, high-fat with EPA) and followed from 2 to 10 months of age. We assessed baseline corticosterone concentration during aging, pain tolerance, cognitive function, stress coping, and corticosterone response to a stressor. RESULTS Transgenic mice were consistently more active than non-transgenic mice but did not perform worse on either cognitive task, even though we recently reported that these same transgenic mice exhibited metabolic changes and had increased amyloid beta. Mice fed high-fat diet had higher baseline and post-stressor corticosterone, but diet did not impact cognition or pain tolerance. Sex had the biggest influence, as female mice were consistently more active and had higher corticosterone than males. CONCLUSION Overall, diet, genotype, and sex did not have consistent impacts on outcomes. We found little support for predicted interactions and correlations, suggesting diet impacts metabolic function and amyloid beta levels, but these outcomes do not translate to changes in behaviors measured here.
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Affiliation(s)
- Breanna N. Harris
- Department of Biological Sciences, Texas Tech University, Lubbock, TX
- Obesity Research Institute, Office of Research & Innovation, Texas Tech University
| | - Mahsa Yavari
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
- Obesity Research Institute, Office of Research & Innovation, Texas Tech University
- Current address: Department of Molecular Metabolism, School of Public Health, Harvard University, Boston, MA
| | - Latha Ramalingam
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
- Obesity Research Institute, Office of Research & Innovation, Texas Tech University
- Current address: Department of Nutritional and Food Studies Syracuse University, Syracuse, NY
| | - P. Logan Mounce
- Department of Biological Sciences, Texas Tech University, Lubbock, TX
| | | | - Angela C. Chavira
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
| | - Sarah Thomas
- Department of Biological Sciences, Texas Tech University, Lubbock, TX
| | - Shane Scoggin
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
| | - Caroline Biltz
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
| | - Naima Moustaid-Moussa
- Department of Nutritional Sciences, Texas Tech University, Lubbock, TX
- Obesity Research Institute, Office of Research & Innovation, Texas Tech University
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Orock A, Johnson A, Mohammadi E, Greenwood-Van Meerveld B. Environmental enrichment reverses stress-induced changes in the brain-gut axis to ameliorate chronic visceral and somatic hypersensitivity. Neurobiol Stress 2024; 28:100590. [PMID: 38075024 PMCID: PMC10698671 DOI: 10.1016/j.ynstr.2023.100590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 11/02/2023] [Accepted: 11/12/2023] [Indexed: 02/12/2024] Open
Abstract
Introduction Behavioral therapies, including cognitive behavioral therapy, hypnotherapy and stress management activities, have emerged as effective treatments for irritable bowel syndrome (IBS), a female predominant disorder of the brain-gut axis. IBS, affecting over 10% of the global population, typically presents with abnormal bowel habits and abdominal pain due to visceral hypersensitivity. While the mechanisms underlying how behavioral therapies treat IBS are still elusive, we had previously shown that chronic stress alters gene expression in brain regions critical for stress processing and nociception. We found that exposure to an enriched environment (EE), the rodent analogue of behavioral therapies, prior to and during the stressor was sufficient to prevent stress-induced changes in glucocorticoid receptor (GR) expression in the central nucleus of the amygdala (CeA) and hippocampus. Pre-exposure to EE also inhibited stress-induced increased colonic permeability and was able to block the induction of stress-induced visceral and somatic hypersensitivity. However, it remains unknown if EE can reverse chronic viscerosomatic hypersensitivity that persists following exposure to stress. We hypothesized that EE after chronic stress would be sufficient to reverse stress-induced changes in i) GR expression in the CeA and hippocampus, ii) ameliorate stress-induced colonic hyperpermeability and iii) restore normal visceral and somatic sensitivity in male and female rats. Methods Male and female rats were exposed to daily water avoidance stress (WAS). After confirming the rats had developed visceral hypersensitivity, 50% of the animals were housed in EE for 2 weeks while the other 50% remained in standard housing (SH). At the end of this period, we assessed visceral and somatic sensitivity. We also collected colon tissue to measure colonic permeability. Micro-punches of tissue from the CeA and hippocampus were isolated to measure GR expression. Control animals not exposed to WAS were kept in SH for the duration of the study (n = 8 per group). Results In both male and female rats, EE reversed stress-induced visceral (p < 0.001) and somatic (p < 0.01) hypersensitivity when compared to WAS animals housed in SH to levels comparable to control animals. EE exposure also reversed changes in GR expression in both the hippocampus (p < 0.01) and CeA (p < 0.01), normalizing GR expression to control levels. EE exposure ameliorated stress-induced colonic hyperpermeability in both male (p < 0.01) and female (p < 0.01) rats compared to WAS rats in SH. Conclusion Our findings suggest that behavioral therapies are viable therapeutic options for IBS as they can counter the stress-induced pathophysiology underlying IBS symptoms including visceral hypersensitivity, increased colonic permeability and altered gene expression.
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Affiliation(s)
- A. Orock
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - A.C. Johnson
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Veterans Affairs Health Care System, Oklahoma City, OK, USA
| | - E. Mohammadi
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - B. Greenwood-Van Meerveld
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Veterans Affairs Health Care System, Oklahoma City, OK, USA
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Aghighi F, Salami M, Talaei SA. Effect of postnatal environmental enrichment on LTP induction in the CA1 area of hippocampus of prenatally traffic noise-stressed female rats. AIMS Neurosci 2023; 10:269-281. [PMID: 38188003 PMCID: PMC10767064 DOI: 10.3934/neuroscience.2023021] [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: 07/09/2023] [Revised: 09/26/2023] [Accepted: 10/16/2023] [Indexed: 01/09/2024] Open
Abstract
Early-life stress negatively alters mammalian brain programming. Environmental enrichment (EE) has beneficial effects on brain structure and function. This study aimed to evaluate the effects of postnatal environmental enrichment on long-term potentiation (LTP) induction in the hippocampal CA1 area of prenatally stressed female rats. The pregnant Wistar rats were housed in a standard animal room and exposed to traffic noise stress 2 hours/day during the third week of pregnancy. Their offspring either remained intact (ST) or received enrichment (SE) for a month starting from postnatal day 21. The control groups either remained intact (CO) or received enrichment (CE). Basic field excitatory post-synaptic potentials (fEPSPs) were recorded in the CA1 area; then, LTP was induced by high-frequency stimulation. Finally, the serum levels of corticosterone were measured. Our results showed that while the prenatal noise stress decreased the baseline responses of the ST rats when compared to the control rats (P < 0.001), the postnatal EE increased the fEPSPs of both the CE and SE animals when compared to the respective controls. Additionally, high-frequency stimulation (HFS) induced LTP in the fEPSPs of the CO rats (P < 0.001) and failed to induce LTP in the fEPSPs of the ST animals. The enriched condition caused increased potentiation of post-HFS responses in the controls (P < 0.001) and restored the disrupted synaptic plasticity of the CA1 area in the prenatally stressed rats. Likewise, the postnatal EE decreased the elevated serum corticosterone of prenatally stressed offspring (P < 0.001). In conclusion, the postnatal EE restored the stress induced impairment of synaptic plasticity in rats' female offspring.
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Affiliation(s)
| | | | - Sayyed Alireza Talaei
- Physiology Research Center, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, I. R. Iran
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Bohn L, Bierbaum L, Kästner N, von Kortzfleisch VT, Kaiser S, Sachser N, Richter SH. Structural enrichment for laboratory mice: exploring the effects of novelty and complexity. Front Vet Sci 2023; 10:1207332. [PMID: 37841462 PMCID: PMC10570735 DOI: 10.3389/fvets.2023.1207332] [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: 04/17/2023] [Accepted: 09/14/2023] [Indexed: 10/17/2023] Open
Abstract
Providing structural enrichment is a widespread refinement method for laboratory rodents and other animals in captivity. So far, animal welfare research has mostly focused on the effect of increased complexity either by accumulating or combining different enrichment items. However, increasing complexity is not the only possibility to refine housing conditions. Another refinement option is to increase novelty by regularly exchanging known enrichment items with new ones. In the present study, we used pair-housed non-breeding female C57BL/6J and DBA/2N mice to investigate the effect of novelty when applying structural enrichment. We used a double cage system, in which one cage served as home cage and the other as extra cage. While the home cage was furnished in the same way for all mice, in the extra cage we either provided only space with no additional enrichment items (space), a fixed set of enrichment items (complexity), or a changing set of enrichment items (novelty). Over 5 weeks, we assessed spontaneous behaviors, body weight, and extra cage usage as indicators of welfare and preference. Our main results showed that mice with access to structurally enriched extra cages (complexity and novelty) spent more time in their extra cages and complexity mice had lower latencies to enter their extra cages than mice with access to the extra cages without any structural enrichment (space). This indicates that the mice preferred the structurally enriched extra cages over the structurally non-enriched space cages. We found only one statistically significant difference between the novelty and complexity condition: during week 3, novelty mice spent more time in their extra cages than complexity mice. Although we did not detect any other significant differences between the novelty and complexity condition in the present study, more research is required to further explore the potential benefits of novelty beyond complexity.
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Affiliation(s)
- Lena Bohn
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - Louisa Bierbaum
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - Niklas Kästner
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | | | - Sylvia Kaiser
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - Norbert Sachser
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
| | - S. Helene Richter
- Department of Behavioural Biology, Institute of Neuro- and Behavioural Biology, University of Münster, Münster, Germany
- Münster Graduate School of Evolution, University of Münster, Münster, Germany
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Farmer AL, Lewis MH. Reduction of restricted repetitive behavior by environmental enrichment: Potential neurobiological mechanisms. Neurosci Biobehav Rev 2023; 152:105291. [PMID: 37353046 DOI: 10.1016/j.neubiorev.2023.105291] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/04/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023]
Abstract
Restricted repetitive behaviors (RRB) are one of two diagnostic criteria for autism spectrum disorder and common in other neurodevelopmental and psychiatric disorders. The term restricted repetitive behavior refers to a wide variety of inflexible patterns of behavior including stereotypy, self-injury, restricted interests, insistence on sameness, and ritualistic and compulsive behavior. However, despite their prevalence in clinical populations, their underlying causes remain poorly understood hampering the development of effective treatments. Intriguingly, numerous animal studies have demonstrated that these behaviors are reduced by rearing in enriched environments (EE). Understanding the processes responsible for the attenuation of repetitive behaviors by EE should offer insights into potential therapeutic approaches, as well as shed light on the underlying neurobiology of repetitive behaviors. This review summarizes the current knowledge of the relationship between EE and RRB and discusses potential mechanisms for EE's attenuation of RRB based on the broader EE literature. Existing gaps in the literature and future directions are also discussed.
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Affiliation(s)
- Anna L Farmer
- Department of Psychology, University of Florida, Gainesville, FL, USA.
| | - Mark H Lewis
- Department of Psychology, University of Florida, Gainesville, FL, USA; Department of Psychiatry, University of Florida, Gainesville, FL, USA
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Lobina C, Maccioni P, Gessa GL, Colombo G. Exposure to an enriched environment exerts anxiolytic effects in Sardinian alcohol-preferring rats. Behav Brain Res 2023; 452:114557. [PMID: 37390968 DOI: 10.1016/j.bbr.2023.114557] [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: 03/14/2023] [Revised: 05/12/2023] [Accepted: 06/26/2023] [Indexed: 07/02/2023]
Abstract
Exposure to an enriched environment (EE) has been reported to generate multiple beneficial effects in rodents, including - among the many - amelioration of anxiety-related behaviors. The present study investigated whether living in an EE produced anxiolytic effects also in selectively bred Sardinian alcohol-preferring (sP) rats. The relevance of this research question relied on two factors: sP rats displayed an inherent, high anxiety-like state under different experimental conditions; exposure to EE reduced operant, oral alcohol self-administration in sP rats. Starting from weaning, male sP rats were kept under 3 different housing conditions: impoverished environment (IE; single housing with no environmental enrichment); standard environment (SE; 3 rats/cage with no environmental enrichment); EE (6 rats/cage with various elements of environmental enrichment). At the age of approximately 80 days, rats were exposed to an elevated plus maze test for assessment of anxiety-related behaviors. Compared to IE and SE rats, EE rats displayed higher basal levels of exploratory activity (i.e., increased number of entries into closed arms). Compared to IE and SE rats, EE rats also displayed a less "anxious" profile, as suggested by the increase in percent number of entries into open arms (OAs), percent time spent in OAs, number of head dips, and number of end-arm explorations in OAs. These data extend the protective (anxiolytic) effects of EE to a proposed animal model of comorbid alcohol use disorder and anxiety disorders.
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Affiliation(s)
- Carla Lobina
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato, CA, Italy
| | - Paola Maccioni
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato, CA, Italy
| | - Gian Luigi Gessa
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato, CA, Italy
| | - Giancarlo Colombo
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato, CA, Italy.
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Pavlova IV, Broshevitskaya ND, Zaichenko MI, Grigoryan GA. The influence of long-term housing in enriched environment on behavior of normal rats and subjected to neonatal pro-inflammatory challenge. Brain Behav Immun Health 2023; 30:100639. [PMID: 37274935 PMCID: PMC10236189 DOI: 10.1016/j.bbih.2023.100639] [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: 11/29/2022] [Revised: 03/15/2023] [Accepted: 05/07/2023] [Indexed: 06/07/2023] Open
Abstract
It is well known that neonatal pro-inflammatory challenge (NPC) acquire a predisposition to the development of a number of neuropsychiatric diseases: depression, anxiety disorders, autism, attention deficit hyperactivity disorder. Symptoms of these diseases can manifest themselves in adulthood and adolescent after repeated exposure to negative influences. Preventing the development of the negative consequences of NPC is one of the main tasks for researchers. The exposure to an enriched environment (EE) was shown to have anxiolytic, anti-depressive, and pro-cognitive effects. The present work was aimed to investigate the effects of the long-term EE on anxious-depressive and conditioned fear behavior in normal male and female rats and subjected to NPC. The NPC was induced by subcutaneous administration of lipopolysaccharide (LPS, 50 μg/kg) on 3d and 5th PNDs. The control animals received saline (SAL). The rats were placed in the EE from 25 to 120 PND. Animals housed in the standard conditions (STAND) served as controls. In adult female and male rats of the STAND groups, LPS did not affect the anxiety, depressive-like behavior and conditioned fear. The EE increased motor and search activity in males and females. In the open field, the EE reduced anxiety in males of the SAL and LPS groups and in females of SAL groups compared to the STAND housed animals. In the elevated plus maze, the EE decreased anxiety only in males of the SAL group. In the sucrose preference test, the EE did not change sucrose consumption in males and females of SAL and LPS groups, while, in the forced swimming test, the EE reduced depressive-like behavior in females of both SAL and LPS groups. The enrichment decreased the contextual conditioned fear in male and female of SAL groups, but not of the LPS group, and did not affect the cue conditioned fear. The corticosterone reactivity to the forced swimming stress increased in males of the EE groups. The basal level of IL-1beta in blood serum decreased in males of the SAL-EE group. Thus, the EE reduced anxiety in males, depressive-like behavior in females, and contextual conditioned fear in males and females compared to the STAND housed animals. Although the NPC did not affect these behaviors in the STAND groups, LPS prevented the beneficial EE effects on anxiety and conditioned fear. The opposing effects of LPS were dependent on sex and type of testing.
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Affiliation(s)
- Irina V. Pavlova
- Corresponding author. Department of Conditioned Reflexes and Physiology of Emotions, Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, 117485, 5a Butlerov street, Moscow, Russian Federation.
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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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Falkowska M, Ntamati NR, Nevian NE, Nevian T, Acuña MA. Environmental enrichment promotes resilience to neuropathic pain-induced depression and correlates with decreased excitability of the anterior cingulate cortex. Front Behav Neurosci 2023; 17:1139205. [PMID: 37008999 PMCID: PMC10060563 DOI: 10.3389/fnbeh.2023.1139205] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/27/2023] [Indexed: 03/18/2023] Open
Abstract
Depression is a common comorbidity of chronic pain with many patients being affected. However, efficient pharmacological treatment strategies are still lacking. Therefore, it is desirable to find additional alternative approaches. Environmental enrichment has been suggested as a method to alleviate pain-induced depression. However, the neuronal mechanisms of its beneficial effects are still elusive. The anterior cingulate cortex (ACC) plays a central role in processing pain-related negative affect and chronic pain-induced plasticity in this region correlates with depressive symptoms. We studied the consequences of different durations of environmental enrichment on pain sensitivity and chronic pain-induced depression-like behaviors in a mouse model of neuropathic pain. Furthermore, we correlated the behavioral outcomes to the activity levels of pyramidal neurons in the ACC by analyzing their electrophysiological properties ex vivo. We found that early exposure to an enriched environment alone was not sufficient to cause resilience against pain-induced depression-like symptoms. However, extending the enrichment after the injury prevented the development of depression and reduced mechanical hypersensitivity. On the cellular level, increased neuronal excitability was associated with the depressive phenotype that was reversed by the enrichment. Therefore, neuronal excitability in the ACC was inversely correlated to the extended enrichment-induced resilience to depression. These results suggest that the improvement of environmental factors enhanced the resilience to developing chronic pain-related depression. Additionally, we confirmed the association between increased neuronal excitability in the ACC and depression-like states. Therefore, this non-pharmacological intervention could serve as a potential treatment strategy for comorbid symptoms of chronic pain.
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Environmental enrichment augments binge-like alcohol drinking in Sardinian alcohol-preferring rats. Alcohol 2022; 105:1-7. [PMID: 36150612 DOI: 10.1016/j.alcohol.2022.09.003] [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: 08/08/2022] [Revised: 09/05/2022] [Accepted: 09/12/2022] [Indexed: 01/26/2023]
Abstract
Exposure of Sardinian alcohol-preferring (sP) rats to an enriched environment (EE) reduced different aspects of operant alcohol self-administration. The present study was aimed at expanding investigation of the effect of EE exposure upon a model of binge drinking composed of daily 1-h drinking sessions with unpredictable access to multiple alcohol concentrations; binge-like alcohol intakes were observed when the drinking session occurred at the last hours of the dark phase of the light/dark cycle. Starting from postnatal day (PND) 21, male sP rats were kept under three different housing conditions: impoverished environment (IE; single housing with no environmental enrichment); standard environment (SE; 3 rats/cage and no environmental enrichment); EE (6 rats/cage and multiple elements of environmental enrichment). From PND 69, rats were exposed daily to a 1-hour drinking session under the 4-bottle "alcohol (10%, 20%, and 30%, v/v) vs. water" choice regimen, during the dark phase, and with timing of alcohol exposure changed each day. In all three rat groups (IE, SE, and EE), alcohol intake increased progressively as the drinking session moved from the first to last hours of the dark phase. The slope of the regression line was steeper in EE than IE and SE rats, suggestive of higher intakes of alcohol in EE than IE and SE rats when the drinking session occurred over the last hours of the dark phase. These results are discussed hypothesizing that the stressful attributes of alcohol expectation were potentiated by the increased "emotionality" that rats living in a comfortable environment (i.e., EE) may experience when facing new, challenging events or environments. Blood alcohol levels, assessed at the end of a final drinking session occurring at the 12th hour of the dark phase, did not differ among the three rat groups and averaged approximately 150 mg%, confirming that this experimental procedure may generate intoxicating levels of alcohol drinking in sP rats.
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Corredor K, Duran J, Herrera-Isaza L, Forero S, Quintanilla J, Gomez A, Martínez GS, Cardenas FP. Behavioral effects of environmental enrichment on male and female wistar rats with early life stress experiences. Front Physiol 2022; 13:837661. [PMID: 36225294 PMCID: PMC9548697 DOI: 10.3389/fphys.2022.837661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Exposure to adverse childhood experiences or early life stress experiences (ELSs) increase the risk of non-adaptive behaviors and psychopathology in adulthood. Environmental enrichment (EE) has been proposed to minimize these effects. The vast number of methodological variations in animal studies underscores the lack of systematicity in the studies and the need for a detailed understanding of how enrichment interacts with other variables. Here we evaluate the effects of environmental enrichment in male and female Wistar rats exposed to adverse early life experiences (prenatal, postnatal, and combined) on emotional (elevated plus maze), social (social interaction chamber), memory (Morris water maze) and flexibility tasks. Our results—collected from PND 51 to 64—confirmed: 1) the positive effect of environmental enrichment (PND 28–49) on anxiety-like behaviors in animals submitted to ELSs. These effects depended on type of experience and type of enrichment: foraging enrichment reduced anxiety-like behaviors in animals with prenatal and postnatal stress but increased them in animals without ELSs. This effect was sex-dependent: females showed lower anxiety compared to males. Our data also indicated that females exposed to prenatal and postnatal stress had lower anxious responses than males in the same conditions; 2) no differences were found for social interactions; 3) concerning memory, there was a significant interaction between the three factors: A significant interaction for males with prenatal stress was observed for foraging enrichment, while physical enrichment was positive for males with postnatal stress; d) regarding cognitive flexibility, a positive effect of EE was found in animals exposed to adverse ELSs: animals with combined stress and exposed to physical enrichment showed a higher index of cognitive flexibility than those not exposed to enrichment. Yet, within animals with no EE, those exposed to combined stress showed lower flexibility than those exposed to both prenatal stress and no stress. On the other hand, animals with prenatal stress and exposed to foraging-type enrichment showed lower cognitive flexibility than those with no EE. The prenatal stress-inducing conditions used here 5) did not induced fetal or maternal problems and 6) did not induced changes in the volume of the dentate gyrus of the hippocampus.
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Affiliation(s)
- K. Corredor
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
- Centro de Investigación en Biomodelos, Bogotá, Colombia
| | - J.M. Duran
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
| | - L. Herrera-Isaza
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
| | - S. Forero
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
| | - J.P. Quintanilla
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
| | - A. Gomez
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
| | | | - F. P. Cardenas
- Laboratory of Neuroscience and Behavior, Universidad de los Andes, Bogotá, Colombia
- *Correspondence: F. P. Cardenas,
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Takano Y, Umezawa M, Kubota N, Takeda K, Yanagita S. Effects of music exposure during pregnancy on maternal behavior in mother rats. Heliyon 2022; 8:e10029. [PMID: 35991990 PMCID: PMC9382262 DOI: 10.1016/j.heliyon.2022.e10029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 04/15/2022] [Accepted: 07/18/2022] [Indexed: 11/18/2022] Open
Abstract
Several studies have demonstrated the possibility of positive effects of exposure to music during pregnancy on mental function in humans and animals. Although there remains a core belief in the positive effects of music during pregnancy, the underlying neurobehavioral mechanisms of these effects remain unknown. In this study, we aimed to clarify the relationship between maternal nurturing behavior and the oxytocinergic system to elucidate the effect of music on mental health during pregnancy in an experimental investigation using animal models. Pregnant rats were exposed to Mozart sonatas, and their nurturing behavior after delivery was assessed using behavioral analyses. The neural activities of the oxytocinergic system, which are associated with nurturing behavior, were investigated using FosB immunohistochemistry. Music during pregnancy significantly increased the licking behavior of mothers towards pups, which is representative of positive nurturing behavior. In contrast, this alteration in maternal behavior was shown to have no marked effect on the structure or activity of the oxytocinergic system. This study provided possible evidence that exposure to music during pregnancy had a positive effect on postnatal maternal behavior. The results also suggest that the oxytocinergic system, considered a strong candidate for the neural system that regulates maternal behavior, may not be associated with this behavioral change. Understanding the relationship between other neural systems, physiological responses, and nurturing behaviors will provide a more comprehensive explanation of the mechanisms by which music exposure during pregnancy has a positive effect on mental health. Pregnant rats were exposed to Mozart sonatas and their nurturing behavior was investigated. Exposure to music during pregnancy has a positive effect on postnatal maternal behavior. Maternal behavior had no marked effect on the structure or activity of the oxytocinergic neurons.
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Affiliation(s)
- Yurika Takano
- Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Masakazu Umezawa
- Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Department of Materials Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, Katsushika, Tokyo 125-8585, Japan
| | - Natsuko Kubota
- Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Ken Takeda
- Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Faculty of Pharmaceutical Sciences, Sanyo-Onoda City University, Sanyo-Onoda, Yamaguchi 756-0884, Japan
| | - Shinya Yanagita
- Research Institute for Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba 278-8510, Japan
- Corresponding author.
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de Siqueira Mendes FDCC, de Almeida MNF, Falsoni M, Andrade MLF, Felício APG, da Paixão LTVB, Júnior FLDA, Anthony DC, Brites D, Diniz CWP, Sosthenes MCK. The Sedentary Lifestyle and Masticatory Dysfunction: Time to Review the Contribution to Age-Associated Cognitive Decline and Astrocyte Morphotypes in the Dentate Gyrus. Int J Mol Sci 2022; 23:ijms23116342. [PMID: 35683023 PMCID: PMC9180988 DOI: 10.3390/ijms23116342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/15/2022] [Accepted: 05/16/2022] [Indexed: 02/01/2023] Open
Abstract
As aging and cognitive decline progresses, the impact of a sedentary lifestyle on the appearance of environment-dependent cellular morphologies in the brain becomes more apparent. Sedentary living is also associated with poor oral health, which is known to correlate with the rate of cognitive decline. Here, we will review the evidence for the interplay between mastication and environmental enrichment and assess the impact of each on the structure of the brain. In previous studies, we explored the relationship between behavior and the morphological features of dentate gyrus glial fibrillary acidic protein (GFAP)-positive astrocytes during aging in contrasting environments and in the context of induced masticatory dysfunction. Hierarchical cluster and discriminant analysis of GFAP-positive astrocytes from the dentate gyrus molecular layer revealed that the proportion of AST1 (astrocyte arbors with greater complexity phenotype) and AST2 (lower complexity) are differentially affected by environment, aging and masticatory dysfunction, but the relationship is not straightforward. Here we re-evaluated our previous reconstructions by comparing dorsal and ventral astrocyte morphologies in the dentate gyrus, and we found that morphological complexity was the variable that contributed most to cluster formation across the experimental groups. In general, reducing masticatory activity increases astrocyte morphological complexity, and the effect is most marked in the ventral dentate gyrus, whereas the effect of environment was more marked in the dorsal dentate gyrus. All morphotypes retained their basic structural organization in intact tissue, suggesting that they are subtypes with a non-proliferative astrocyte profile. In summary, the increased complexity of astrocytes in situations where neuronal loss and behavioral deficits are present is counterintuitive, but highlights the need to better understand the role of the astrocyte in these conditions.
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Affiliation(s)
- Fabíola de Carvalho Chaves de Siqueira Mendes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
- Curso de Medicina, Centro Universitário do Estado do Pará, Belém 66613-903, PA, Brazil
| | - Marina Negrão Frota de Almeida
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Manoela Falsoni
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Marcia Lorena Ferreira Andrade
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - André Pinheiro Gurgel Felício
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Luisa Taynah Vasconcelos Barbosa da Paixão
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Fábio Leite do Amaral Júnior
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Daniel Clive Anthony
- Laboratory of Experimental Neuropathology, Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK;
| | - Dora Brites
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-004 Lisbon, Portugal;
- Department of Pharmaceutical Sciences and Medicines, Faculty of Pharmacy, Universidade de Lisboa, 1649-004 Lisbon, Portugal
| | - Cristovam Wanderley Picanço Diniz
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
| | - Marcia Consentino Kronka Sosthenes
- Laboratório de Investigações em Neurodegeneração e Infecção, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Universidade Federal do Pará, Belém 66073-005, PA, Brazil; (F.d.C.C.d.S.M.); (M.N.F.d.A.); (M.F.); (M.L.F.A.); (A.P.G.F.); (L.T.V.B.d.P.); (F.L.d.A.J.); (C.W.P.D.)
- Correspondence:
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Environmental Enrichment Components Required to Reduce Methamphetamine-Induced Behavioral Sensitization in Mice: Examination of Behaviors and Neural Substrates. J Clin Med 2022; 11:jcm11113051. [PMID: 35683439 PMCID: PMC9181252 DOI: 10.3390/jcm11113051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/22/2022] [Accepted: 05/26/2022] [Indexed: 01/25/2023] Open
Abstract
Environmental enrichment (EE) involves the presentation of various sensory, physical, social, and cognitive stimuli in order to alter neural activity in specific brain areas, which can ameliorate methamphetamine (MAMPH)-induced behavioral sensitization and comorbid anxiety symptoms. No previous studies have comprehensively examined which EE components are critical for effectively reducing MAMPH-induced behavioral sensitization and anxiety. This study examined different housing conditions, including standard housing (SH, No EE), standard EE (STEE), physical EE (PEE), cognitive EE (CEE), and social EE (SEE). In the beginning, mice were randomly assigned to the different combinations of housing conditions and injections, consisting of No EE/Saline, No EE/MAMPH, STEE/MAMPH, PEE/MAMPH, CEE/MAMPH, and SEE/MAMPH groups. Then, the mice received intraperitoneal injections of 1 mg/kg MAMPH or normal saline daily for 7 days, followed by a final injection of 0.5 mg/kg MAMPH or normal saline. After behavioral tests, all mice were examined for c-Fos immunohistochemical staining. The results showed that MAMPH induced behavioral sensitization as measured by distance traveled. MAMPH appeared to induce lowered anxiety responses and severe hyperactivity. All EE conditions did not affect MAMPH-induced lowered anxiety behaviors. STEE was likely more effective for reducing MAMPH-induced behavioral sensitization than PEE, CEE, and SEE. The c-Fos expression analysis showed that the medial prefrontal cortex (i.e., cingulate cortex 1 (Cg1), prelimbic cortex (PrL), and infralimbic cortex (IL)), nucleus accumbens (NAc), basolateral amygdala (BLA), ventral tegmental area (VTA), caudate-putamen (CPu), and hippocampus (i.e., CA1, CA3, and dentate gyrus (DG)) contributed to MAMPH-induced behavioral sensitization. The Cg1, IL, NAc, BLA, VTA, CPu, CA3, and DG also mediated STEE reductions in MAMPH-induced behavioral sensitization. This study indicates that all components of EE are crucial for ameliorating MAMPH-induced behavioral sensitization, as no individual EE component was able to effectively reduce MAMPH-induced behavioral sensitization. The present findings provide insight into the development of non-pharmacological interventions for reducing MAMPH-induced behavioral sensitization.
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Maccioni P, Bratzu J, Lobina C, Acciaro C, Corrias G, Capra A, Carai MAM, Agabio R, Muntoni AL, Gessa GL, Colombo G. Exposure to an enriched environment reduces alcohol self-administration in Sardinian alcohol-preferring rats. Physiol Behav 2022; 249:113771. [PMID: 35247441 DOI: 10.1016/j.physbeh.2022.113771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 02/28/2022] [Accepted: 02/28/2022] [Indexed: 10/19/2022]
Abstract
Living in an enriched environment (EE) produces a notable impact on several rodent behaviors, including those motivated by drugs of abuse. This picture is somewhat less clear when referring to alcohol-motivated behaviors. With the intent of contributing to this research field with data from one of the few rat lines selectively bred for excessive alcohol consumption, the present study investigated the effect of EE on operant oral alcohol self-administration in Sardinian alcohol-preferring (sP) rats. Starting from Postnatal Day (PND) 21, male sP rats were kept under 3 different housing conditions: impoverished environment (IE; single housing in shoebox-like cages with no environmental enrichment); standard environment (SE; small colony cages with 3 rats and no environmental enrichment); EE (large colony cages with 6 rats and multiple elements of environmental enrichment, including 2 floors, ladders, maze, running wheels, and shelter). From PND 60, rats were exposed to different phases of shaping and training of alcohol self-administration. IE, SE, and EE rats were then compared under (i) fixed ratio (FR) 4 (FR4) schedule of alcohol reinforcement for 20 daily sessions and (ii) progressive ratio (PR) schedule of alcohol reinforcement in a final single session. Acquisition of the lever-responding task (shaping) was slower in EE than IE and SE rats, as the likely consequence of a "devaluation" of the novel stimuli provided by the operant chamber in comparison to those to which EE rats were continuously exposed in their homecage or an alteration, induced by EE, of the rat "emotionality" state when facing the novel environment represented by the operant chamber. Training of alcohol self-administration was slower in EE than IE rats, with SE rats displaying intermediate values. A similar ranking order (IE>SE>EE) was also observed in number of lever-responses for alcohol, amount of self-administered alcohol, and breakpoint for alcohol under FR4 and PR schedules of reinforcement. These data suggest that living in a complex environment reduced the reinforcing and motivational properties of alcohol in sP rats. These results are interpreted in terms of the reinforcing and motivational properties of the main components of EE (i.e., social interactions, physical activities, exploration, novelty) substituting, at least partially, for those of alcohol.
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Affiliation(s)
- Paola Maccioni
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy
| | - Jessica Bratzu
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy
| | - Carla Lobina
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy
| | - Carla Acciaro
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy
| | - Gianluigi Corrias
- Department of Physics, University of Cagliari, I-09042 Monserrato (CA), Italy
| | - Alessandro Capra
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, I-09042 Monserrato (CA), Italy
| | - Mauro A M Carai
- Cagliari Pharmacological Research, I-09127 Cagliari (CA), Italy
| | - Roberta Agabio
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, I-09042 Monserrato (CA), Italy
| | - Anna Lisa Muntoni
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy
| | - Gian Luigi Gessa
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy; Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, I-09042 Monserrato (CA), Italy
| | - Giancarlo Colombo
- Neuroscience Institute, Section of Cagliari, National Research Council of Italy, I-09042 Monserrato (CA), Italy.
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Harry GJ, McBride S, Witchey SK, Mhaouty-Kodja S, Trembleau A, Bridge M, Bencsik A. Roadbumps at the Crossroads of Integrating Behavioral and In Vitro Approaches for Neurotoxicity Assessment. FRONTIERS IN TOXICOLOGY 2022; 4:812863. [PMID: 35295216 PMCID: PMC8915899 DOI: 10.3389/ftox.2022.812863] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/25/2022] [Indexed: 12/15/2022] Open
Abstract
With the appreciation that behavior represents the integration and complexity of the nervous system, neurobehavioral phenotyping and assessment has seen a renaissance over the last couple of decades, resulting in a robust database on rodent performance within various testing paradigms, possible associations with human disorders, and therapeutic interventions. The interchange of data across behavior and other test modalities and multiple model systems has advanced our understanding of fundamental biology and mechanisms associated with normal functions and alterations in the nervous system. While there is a demonstrated value and power of neurobehavioral assessments for examining alterations due to genetic manipulations, maternal factors, early development environment, the applied use of behavior to assess environmental neurotoxicity continues to come under question as to whether behavior represents a sensitive endpoint for assessment. Why is rodent behavior a sensitive tool to the neuroscientist and yet, not when used in pre-clinical or chemical neurotoxicity studies? Applying new paradigms and evidence on the biological basis of behavior to neurobehavioral testing requires expertise and refinement of how such experiments are conducted to minimize variability and maximize information. This review presents relevant issues of methods used to conduct such test, sources of variability, experimental design, data analysis, interpretation, and reporting. It presents beneficial and critical limitations as they translate to the in vivo environment and considers the need to integrate across disciplines for the best value. It proposes that a refinement of behavioral assessments and understanding of subtle pronounced differences will facilitate the integration of data obtained across multiple approaches and to address issues of translation.
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Affiliation(s)
- G. Jean Harry
- Neurotoxicology Group, Molecular Toxicology Branch, Division National Toxicology Program, National Institute of Environmental Health Sciences, Durham, NC, United States
- *Correspondence: G. Jean Harry,
| | - Sandra McBride
- Social & Scientific Systems, Inc., a DLH Holdings Company, Durham, NC, United States
| | - Shannah K. Witchey
- Division National Toxicology Program, National Institute of Environmental Health Sciences, Durham, NC, United States
| | - Sakina Mhaouty-Kodja
- Sorbonne Université, CNRS, INSERM, Neuroscience Paris Seine – Institut de Biologie Paris Seine, Paris, France
| | - Alain Trembleau
- Sorbonne Université, CNRS UMR8246, Inserm U1130, Institut de Biologie Paris Seine (IBPS), Neuroscience Paris Seine (NPS), Paris, France
| | - Matthew Bridge
- Social & Scientific Systems, Inc., a DLH Holdings Company, Durham, NC, United States
| | - Anna Bencsik
- Anses Laboratoire de Lyon, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université de Lyon 1, Lyon, France
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Macartney EL, Lagisz M, Nakagawa S. The Relative Benefits of Environmental Enrichment on Learning and Memory are Greater When Stressed: A Meta-analysis of Interactions in Rodents. Neurosci Biobehav Rev 2022; 135:104554. [PMID: 35149103 DOI: 10.1016/j.neubiorev.2022.104554] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/24/2022] [Accepted: 01/30/2022] [Indexed: 12/11/2022]
Abstract
Environmental enrichment ("EE") is expected to alleviate the negative effects of stress on cognitive performance. However, there are complexities associated with interpreting interactions that obscure determining the benefit EE may play in mitigating the negative effects of stress. To clarify these complexities, we conducted a systematic review with meta-analysis on the main and interactive effects of EE and stress on learning and memory in rodents. We show that EE and stress interact 'synergistically' where EE provides a greater relative benefit to stressed individuals compared to those reared in conventional housing. Importantly, EE can fully-compensate for the negative effects of stress where stressed individuals with EE performed equally to enriched individuals without a stress manipulation. Additionally, we show the importance of other mediating factors, including the order of treatment exposure, duration and type of stress, type of EE, and type of cognitive assays used. This study not only quantifies the interactions between EE and stress, but also provides a clear example for how to conduct and interpret meta-analysis of interactions.
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Affiliation(s)
- Erin L Macartney
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia Kensington Campus, UNSW, Sydney, NSW 2052.
| | - Malgorzata Lagisz
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia Kensington Campus, UNSW, Sydney, NSW 2052
| | - Shinichi Nakagawa
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia Kensington Campus, UNSW, Sydney, NSW 2052
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21
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The Medial Prefrontal Cortex, Nucleus Accumbens, Basolateral Amygdala, and Hippocampus Regulate the Amelioration of Environmental Enrichment and Cue in Fear Behavior in the Animal Model of PTSD. Behav Neurol 2022; 2022:7331714. [PMID: 35178125 PMCID: PMC8843982 DOI: 10.1155/2022/7331714] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 01/07/2022] [Accepted: 01/27/2022] [Indexed: 11/21/2022] Open
Abstract
A growing body of evidence showed that environmental enrichment (EE) ameliorated footshock-induced fear behavior of posttraumatic stress disorder (PTSD). However, no research comprehensively tested the effect of EE, cue, and the combination of EE and cue in footshock-induced fear behavior of PTSD symptoms. The present study addressed this issue and examined whether the medial prefrontal cortex (mPFC, including the cingulate cortex 1 (Cg1), prelimbic cortex (PrL), and infralimbic cortex (IL)), the nucleus accumbens (NAc), the basolateral amygdala (BLA), and the hippocampus (e.g., CA1, CA3, and dentate gyrus (DG)) regulated the amelioration of the EE, cue, or the combination of EE and cue. The results showed that EE or cue could reduce fear behavior. The combination of EE and cue revealed a stronger decrease in fear behavior. The cue stimulus may play an occasion setting or a conditioned stimulus to modulate the reduction in fear behavior induced by footshock. Regarding the reduction of the EE in fear behavior, the Cg1 and IL of the mPFC and the NAc upregulated the c-Fos expression; however, the BLA downregulated the c-Fos expression. The mPFC (i.e., the Cg1, PrL, and IL) and the hippocampus (i.e., the CA1, CA3, and DG) downregulated the c-Fos expression in the suppression of the cue in fear behavior. The interaction of EE and cue in reduction of fear behavior occurred in the Cg1 and NAc for the c-Fos expression. The data of c-Fos mRNA were similar to the findings of the c-Fos protein expression. These findings related to the EE and cue modulations in fear behavior may develop a novel nonpharmacological treatment in PTSD.
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22
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Cosgrove JA, Kelly LK, Kiffmeyer EA, Kloth AD. Sex-dependent influence of postweaning environmental enrichment in Angelman syndrome model mice. Brain Behav 2022; 12:e2468. [PMID: 34985196 PMCID: PMC8865162 DOI: 10.1002/brb3.2468] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 11/09/2021] [Accepted: 12/12/2021] [Indexed: 12/31/2022] Open
Abstract
INTRODUCTION Angelman syndrome (AS) is a rare neurodevelopmental disorder caused by mutation or loss of UBE3A and marked by intellectual disability, ataxia, autism-like symptoms, and other atypical behaviors. One route to treatment may lie in the role that environment plays early in postnatal life. Environmental enrichment (EE) is one manipulation that has shown therapeutic potential in preclinical models of many brain disorders, including neurodevelopmental disorders. Here, we examined whether postweaning EE can rescue behavioral phenotypes in Ube3a maternal deletion mice (AS mice), and whether any improvements are sex-dependent. METHODS Male and female mice (C57BL/6J Ube3atm1Alb mice and wild-type (WT) littermates; ≥10 mice/group) were randomly assigned to standard housing (SH) or EE at weaning. EE had a larger footprint, a running wheel, and a variety of toys that promoted foraging, burrowing, and climbing. Following 6 weeks of EE, animals were submitted to a battery of tests that reliably elicit behavioral deficits in AS mice, including rotarod, open field, marble burying, and forced swim; weights were also monitored. RESULTS In male AS-EE mice, we found complete restoration of motor coordination, marble burying, and forced swim behavior to the level of WT-SH mice. We also observed a complete normalization of exploratory distance traveled in the open field, but we found no rescue of vertical behavior or center time. AS-EE mice also had weights comparable to WT-SH mice. Intriguingly, in the female AS-EE mice, we found a failure of EE to rescue the same behavioral deficits relative to female WT-SH mice. CONCLUSIONS Environmental enrichment is an effective route to correcting the most penetrant phenotypes in male AS mice but not female AS mice. This finding has important implications for the translatability of early behavioral intervention for AS patients, most importantly the potential dependency of treatment response on sex.
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Affiliation(s)
- Jameson A. Cosgrove
- Department of BiologyAugustana University2001 S. Summit AvenueSioux FallsSouth DakotaUSA
| | - Lauren K. Kelly
- Department of BiologyAugustana University2001 S. Summit AvenueSioux FallsSouth DakotaUSA
| | - Elizabeth A. Kiffmeyer
- Department of BiologyAugustana University2001 S. Summit AvenueSioux FallsSouth DakotaUSA
| | - Alexander D. Kloth
- Department of BiologyAugustana University2001 S. Summit AvenueSioux FallsSouth DakotaUSA
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23
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Orock A, Louwies T, Ligon CO, Mohammadi E, Greenwood-Van Meerveld B. Environmental enrichment prevents stress-induced epigenetic changes in the expression of glucocorticoid receptor and corticotrophin releasing hormone in the central nucleus of the amygdala to inhibit visceral hypersensitivity. Exp Neurol 2021; 345:113841. [PMID: 34390704 DOI: 10.1016/j.expneurol.2021.113841] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 07/01/2021] [Accepted: 08/09/2021] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Stress is a known trigger for the symptoms of irritable bowel syndrome (IBS), a gastrointestinal (GI) disorder that presents with abnormal bowel habits and abdominal pain due to visceral hypersensitivity. While behavioral therapies have been used to attenuate IBS symptoms, the underlying mechanisms by which these therapies interact with stress-induced pathology remains to be delineated. Here we use a rat model to test the hypothesis that exposure to environmental enrichment (EE) inhibits stress-induced changes within the brain-gut axis to prevent visceral and somatic hypersensitivity and colonic hyperpermeability. METHODS Female rats (n = 8/group) were housed in EE one week before and one week during exposure to water avoidance stress (WAS) while controls were housed in standard cages (SH). One day after the final WAS exposure, colonic and somatic sensitivity were assessed by the visceromotor response (VMR) to colorectal distension (CRD) and withdrawal threshold elicited by an electronic von Frey on the hind paw of the rats respectively. All rats were returned to SH for 3 weeks before colonic and somatic sensitivity were reassessed on day 28. The rats were then immediately euthanized and the spinal cord was collected to assess changes in neuronal activation (assessed via ERK phosphorylation) in response to noxious CRD. A separate cohort of animals (n = 8/group) that did not undergo behavioral assessments was euthanized the day after the final WAS exposure and the central nucleus of the amygdala (CeA) was collected to investigate WAS and EE induced epigenetic changes at the glucocorticoid receptor (GR) and corticotrophin releasing hormone (CRH) promoter. The colon from these rats was also collected to assess colonic permeability via changes in transepithelial electrical resistance (TEER) in vitro. RESULTS Exposure to stress persistently increased VMR to CRD (P < 0.01) and decreased the hind paw withdrawal threshold (P < 0.001) in female rats. WAS also decreased TEER in the colon tissue of female rats (p = 0.05). In the CeA, WAS induced a decrease in histone acetylation at the GR promoter but increased histone acetylation at the CRH promoter and reduced GR-CRH interactions in the CeA. Analysis of the spinal cord showed that WAS increased CRD-evoked ERK phosphorylation in the dorsal horn. Exposure to EE prevented WAS-induced changes in the CeA, dorsal horn and colon respectively to prevent visceral and somatic hypersensitivity. CONCLUSION Our data reveals that behavioral therapies can produce long lasting molecular and epigenetic changes that can prevent stress-induced pathologies even after completion of the therapy. These results highlight the potential mechanisms by which behavioral therapies may ameliorate visceral pain associated stress-related pathologies such as the irritable bowel syndrome.
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Affiliation(s)
- A Orock
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America.
| | - T Louwies
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America
| | - C O Ligon
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America
| | - E Mohammadi
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America
| | - B Greenwood-Van Meerveld
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States of America; Department of Veterans Affairs Health Care System, Oklahoma City, OK, United States of America
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24
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Rojas-Carvajal M, Sequeira-Cordero A, Brenes JC. The environmental enrichment model revisited: A translatable paradigm to study the stress of our modern lifestyle. Eur J Neurosci 2021; 55:2359-2392. [PMID: 33638921 DOI: 10.1111/ejn.15160] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 01/31/2021] [Accepted: 02/14/2021] [Indexed: 01/31/2023]
Abstract
Mounting evidence shows that physical activity, social interaction and sensorimotor stimulation provided by environmental enrichment (EE) exert several neurobehavioural effects traditionally interpreted as enhancements relative to standard housing (SH) conditions. However, this evidence rather indicates that SH induces many deficits, which could be ameliorated by exposing animals to an environment vaguely mimicking some features of their wild habitat. Rearing rodents in social isolation (SI) can aggravate such deficits, which can be restored by SH or EE. It is not surprising, therefore, that most preclinical stress models have included severe and unnatural stressors to produce a stress response prominent enough to be distinguishable from SH or SI-frequently used as control groups. Although current stress models induce a stress-related phenotype, they may fail to represent the stress of our urban lifestyle characterized by SI, poor housing and working environments, sedentarism, obesity and limited access to recreational activities and exercise. In the following review, we discuss the stress of living in urban areas and how exposures to and performing activities in green environments are stress relievers. Based on the commonalities between human and animal EE, we discuss how models of housing conditions (e.g., SI-SH-EE) could be adapted to study the stress of our modern lifestyle. The housing conditions model might be easy to implement and replicate leading to more translational results. It may also contribute to accomplishing some ethical commitments by promoting the refinement of procedures to model stress, diminishing animal suffering, enhancing animal welfare and eventually reducing the number of experimental animals needed.
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Affiliation(s)
- Mijail Rojas-Carvajal
- Instituto de Investigaciones Psicológicas, Universidad de Costa Rica, San Pedro, Costa Rica.,Centro de Investigación en Neurociencias, Universidad de Costa Rica, San Pedro, Costa Rica
| | - Andrey Sequeira-Cordero
- Centro de Investigación en Neurociencias, Universidad de Costa Rica, San Pedro, Costa Rica.,Instituto de Investigaciones en Salud, Universidad de Costa Rica, San Pedro, Costa Rica
| | - Juan C Brenes
- Instituto de Investigaciones Psicológicas, Universidad de Costa Rica, San Pedro, Costa Rica.,Centro de Investigación en Neurociencias, Universidad de Costa Rica, San Pedro, Costa Rica
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25
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Hua M, Min J. Postoperative Cognitive Dysfunction and the Protective Effects of Enriched Environment: A Systematic Review. NEURODEGENER DIS 2021; 20:113-122. [PMID: 33601385 DOI: 10.1159/000513196] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 11/17/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Currently, the number of individuals who undergo surgery is greatly increased. As a consequence, postoperative cognitive dysfunction (POCD) has gradually gained more attention. SUMMARY POCD is a perioperative complication requiring sensitive preoperative and postoperative neuropsychiatric tests, and its incidence in both cardiac and noncardiac surgery is high, especially in elderly individuals. Surgical, patient, and anesthetic factors may all lead to the occurrence and development of POCD. The key mechanism of POCD may be the inflammatory response of the central nervous system during surgery, which is similar to that of Alzheimer's disease (AD). Enriched environment (EE), a factor that can significantly improve and prevent neurodegenerative diseases, may have a beneficial effect on POCD. Key Messages: This review aims to elucidate the mechanism of the occurrence and development of POCD, analyze the possible influence of EE on POCD at the molecular level, and provide a direction for its treatment.
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Affiliation(s)
- Momin Hua
- First Clinical Medical College, Nanchang University, Nanchang, China
| | - Jia Min
- Department of Anesthesiology, First Affiliated Hospital of Nanchang University, Nanchang, China,
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26
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Pritchett-Corning KR. Environmental Complexity and Research Outcomes. ILAR J 2020; 60:239-251. [PMID: 32559304 DOI: 10.1093/ilar/ilaa007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 01/28/2020] [Accepted: 02/04/2020] [Indexed: 11/14/2022] Open
Abstract
Environmental complexity is an experimental paradigm as well as a potential part of animals' everyday housing experiences. In experimental uses, researchers add complexity to stimulate brain development, delay degenerative brain changes, elicit more naturalistic behaviors, and test learning and memory. Complexity can exacerbate or mitigate behavioral problems, give animals a sense of control, and allow for expression of highly driven, species-typical behaviors that can improve animal welfare. Complex environments should be designed thoughtfully with the animal's natural behaviors in mind, reported faithfully in the literature, and evaluated carefully for unexpected effects.
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Affiliation(s)
- Kathleen R Pritchett-Corning
- Office of Animal Resources, Faculty of Arts and Sciences, Harvard University, Cambridge, Massachusetts.,Department of Comparative Medicine, University of Washington, Seattle, Washington
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27
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Smail MA, Smith BL, Nawreen N, Herman JP. Differential impact of stress and environmental enrichment on corticolimbic circuits. Pharmacol Biochem Behav 2020; 197:172993. [PMID: 32659243 PMCID: PMC7484282 DOI: 10.1016/j.pbb.2020.172993] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 05/27/2020] [Accepted: 07/02/2020] [Indexed: 12/12/2022]
Abstract
Stress exposure can produce profound changes in physiology and behavior that can impair health and well-being. Of note, stress exposure is linked to anxiety disorders and depression in humans. The widespread impact of these disorders warrants investigation into treatments to mitigate the harmful effects of stress. Pharmacological treatments fail to help many with these disorders, so recent work has focused on non-pharmacological alternatives. One of the most promising of these alternatives is environmental enrichment (EE). In rodents, EE includes social, physical, and cognitive stimulation for the animal, in the form of larger cages, running wheels, and toys. EE successfully reduces the maladaptive effects of various stressors, both as treatment and prophylaxis. While we know that EE can have beneficial effects under stress conditions, the morphological and molecular mechanisms underlying these behavioral effects are still not well understood. EE is known to alter neurogenesis, dendrite development, and expression of neurotrophic growth factors, effects that vary by type of enrichment, age, and sex. To add to this complexity, EE has differential effects in different brain regions. Understanding how EE exerts its protective effects on morphological and molecular levels could hold the key to developing more targeted pharmacological treatments. In this review, we summarize the literature on the morphological and molecular consequences of EE and stress in key emotional regulatory pathways in the brain, the hippocampus, prefrontal cortex, and amygdala. The similarities and differences among these regions provide some insight into stress-EE interaction that may be exploited in future efforts toward prevention of, and intervention in, stress-related diseases.
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Affiliation(s)
- Marissa A Smail
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH, United States.
| | - Brittany L Smith
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Nawshaba Nawreen
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH, United States
| | - James P Herman
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Veterans Affairs Medical Center, Cincinnati, OH, United States; Department of Neurology, University of Cincinnati, Cincinnati, OH, United States
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Vogt MA, Mertens S, Serba S, Palme R, Chourbaji S. The ‘Cage Climber’ - A new enrichment for use in large-dimensioned mouse facilities. Appl Anim Behav Sci 2020. [DOI: 10.1016/j.applanim.2020.105078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Sparling JE, Barbeau K, Boileau K, Konkle ATM. Environmental enrichment and its influence on rodent offspring and maternal behaviours, a scoping style review of indices of depression and anxiety. Pharmacol Biochem Behav 2020; 197:172997. [PMID: 32702399 DOI: 10.1016/j.pbb.2020.172997] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 07/05/2020] [Accepted: 07/09/2020] [Indexed: 12/30/2022]
Abstract
Environmental enrichment is a widely used experimental manipulation that consistently shows measurable effects on rodent behaviour across the lifespan. This scoping review assesses and thematically summarizes the literature of the past decade concerning the effects of environmental enrichment applied during sensitive developmental periods in rodent mothers and offspring. Maternal behaviours as well as maternal and offspring anxiety- and depressive-like behaviours are considered. Relevant terms were searched across five databases (Embase, MEDLINE, PsycINFO, PubMed, Web of Science) and articles were screened with inclusion and exclusion criteria. The remaining articles were thematically analysed. Our results suggest that a greater number of articles reviewed the impacts of environmental enrichment on offspring anxiety-like behaviour (n = 23) rather than on depressive-like behaviour (n = 11) or maternal caregiving behaviour (n = 12). Maternal anxiety- (n = 4) or depressive-like (n = 2) behaviours are not often evaluated for in enrichment studies. The main behavioural tests of anxiety that were reviewed include the elevated plus-maze, the open field test, and the light-dark box whereas those for depression included the forced swim test and the sucrose preference test. Our results yielded mixed findings and significant variation in behavioural responses across all tests. In mothers, trends of increased maternal care behaviours and decreased maternal depressive-like behaviours in enriched mothers were appreciated. Enrichment during the gestational period was identified as pivotal to creating behavioural change in mother subjects. In enriched offspring rodents, a trend towards decreased anxiety-like behaviours was observed most often. Potential confounds inherent in enrichment paradigms and relevant theories of enrichment and their relation to rodent behavioural tests are discussed.
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Affiliation(s)
- Jessica E Sparling
- School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; Department of Psychiatry, University of Calgary, Calgary, Alberta, Canada.
| | - Kheana Barbeau
- School of Psychology, University of Ottawa, Ottawa, Ontario, Canada.
| | - Kayla Boileau
- School of Psychology, University of Ottawa, Ottawa, Ontario, Canada.
| | - Anne T M Konkle
- School of Psychology, University of Ottawa, Ottawa, Ontario, Canada; Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Ontario, Canada; University of Ottawa Brain and Mind Research Institute, Ottawa, Ontario, Canada.
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30
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Lang GP, Rose PE, Nash SM, Riley LM. The nocturnal activity of a commonly housed rodent: How African pygmy dormice (Graphiurus murinus) respond to an enriched environment? J Vet Behav 2020. [DOI: 10.1016/j.jveb.2020.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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31
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Law M, Jarrett P, Nater UM, Skoluda N, Broadbent E. The effects of environmental enrichment on skin barrier recovery in humans: a randomised trial. Sci Rep 2020; 10:9829. [PMID: 32555211 PMCID: PMC7299948 DOI: 10.1038/s41598-020-66687-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Accepted: 05/23/2020] [Indexed: 12/16/2022] Open
Abstract
This study investigated whether environmental enrichment (EE) could reduce stress and improve wound healing in humans. 120 participants underwent a standardised tape-stripping procedure and were then randomised to interact for 30 minutes with one of three EE interventions (comfort blankets as tactile enrichment, music as auditory enrichment or a Paro robot as multi-sensory enrichment) or to a control group. Skin barrier recovery (SBR) was measured using transepidermal water loss at baseline, after tape-stripping and after the intervention. Psychological variables, cortisol and alpha-amylase were measured at the three time-points. SBR did not significantly differ between the EE conditions and the control condition. The music condition had higher stimulation levels than the control condition, and the comfort condition had significantly lower relaxation levels than the control condition after the intervention. The EE interventions tested were not beneficial for wound healing compared to a control group. Limitations were that the sample were not stressed and an active control condition was used.
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Affiliation(s)
- Mikaela Law
- Department of Psychological Medicine, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Paul Jarrett
- Department of Dermatology, Middlemore Hospital, Auckland, New Zealand.,Department of Medicine, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand
| | - Urs M Nater
- Faculty of Psychology, University of Vienna, Vienna, 1010, Austria
| | - Nadine Skoluda
- Faculty of Psychology, University of Vienna, Vienna, 1010, Austria
| | - Elizabeth Broadbent
- Department of Psychological Medicine, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand.
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Experience Recruits MSK1 to Expand the Dynamic Range of Synapses and Enhance Cognition. J Neurosci 2020; 40:4644-4660. [PMID: 32376781 PMCID: PMC7294801 DOI: 10.1523/jneurosci.2765-19.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 12/29/2022] Open
Abstract
Experience powerfully influences neuronal function and cognitive performance, but the cellular and molecular events underlying the experience-dependent enhancement of mental ability have remained elusive. In particular, the mechanisms that couple the external environment to the genomic changes underpinning this improvement are unknown. To address this, we have used male mice harboring an inactivating mutation of mitogen- and stress-activated protein kinase 1 (MSK1), a brain-derived neurotrophic factor (BDNF)-activated enzyme downstream of the mitogen-activated protein kinase (MAPK) pathway. We show that MSK1 is required for the full extent of experience-induced improvement of spatial memory, for the expansion of the dynamic range of synapses, exemplified by the enhancement of hippocampal long-term potentiation (LTP) and long-term depression (LTD), and for the regulation of the majority of genes influenced by enrichment. In addition, and unexpectedly, we show that experience is associated with an MSK1-dependent downregulation of key MAPK and plasticity-related genes, notably of EGR1/Zif268 and Arc/Arg3.1, suggesting the establishment of a novel genomic landscape adapted to experience. By coupling experience to homeostatic changes in gene expression MSK1, represents a prime mechanism through which the external environment has an enduring influence on gene expression, synaptic function, and cognition. SIGNIFICANCE STATEMENT Our everyday experiences strongly influence the structure and function of the brain. Positive experiences encourage the growth and development of the brain and support enhanced learning and memory and resistance to mood disorders such as anxiety. While this has been known for many years, how this occurs is not clear. Here, we show that many of the positive aspects of experience depend on an enzyme called mitogen- and stress-activated protein kinase 1 (MSK1). Using male mice with a mutation in MSK1, we show that MSK1 is necessary for the majority of gene expression changes associated with experience, extending the range over which the communication between neurons occurs, and for both the persistence of memory and the ability to learn new task rules.
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Abstract
The Norway rat has important impacts on our life. They are amongst the most used research subjects, resulting in ground-breaking advances. At the same time, wild rats live in close association with us, leading to various adverse interactions. In face of this relevance, it is surprising how little is known about their natural behaviour. While recent laboratory studies revealed their complex social skills, little is known about their social behaviour in the wild. An integration of these different scientific approaches is crucial to understand their social life, which will enable us to design more valid research paradigms, develop more effective management strategies, and to provide better welfare standards. Hence, I first summarise the literature on their natural social behaviour. Second, I provide an overview of recent developments concerning their social cognition. Third, I illustrate why an integration of these areas would be beneficial to optimise our interactions with them.
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Affiliation(s)
- Manon K Schweinfurth
- School of Psychology and Neuroscience, University of St AndrewsSt AndrewsUnited Kingdom
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Emmerson MG, Spencer KA, Brown GR. Social experience during adolescence in female rats increases 50 kHz ultrasonic vocalizations in adulthood, without affecting anxiety-like behavior. Dev Psychobiol 2019; 62:212-223. [PMID: 31429082 DOI: 10.1002/dev.21906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 07/01/2019] [Accepted: 07/16/2019] [Indexed: 01/28/2023]
Abstract
Adolescents are highly motivated to engage in social interactions, and researchers have hypothesized that positive social relationships during adolescence can have long term, beneficial effects on stress reactivity and mental well-being. Studies of laboratory rodents provide the opportunity to investigate the relationship between early social experiences and later behavioral and physiological responses to stressors. In this study, female Lister-hooded rats (N = 12 per group) were either (a) provided with short, daily encounters (10 min/day) with a novel partner during mid-adolescence (postnatal day 34-45; "social experience," SE, subjects) or (b) underwent the same protocol with a familiar cagemate during mid-adolescence ("control experience," CE, subjects), or (c) were left undisturbed in the home cage (non-handled "control," C, subjects). When tested in adulthood, the groups did not differ in behavioral responses to novel environments (elevated plus maze, open field, and light-dark box) or in behavioral and physiological (urinary corticosterone) responses to novel social partners. However, SE females emitted significantly more 50 kHz ultrasonic vocalizations than control subjects both before and after social separation from a familiar social partner, which is consistent with previous findings in male rats. Thus, enhanced adolescent social experience appears to have long-term effects on vocal communication and could potentially modulate adult social relationships.
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Affiliation(s)
| | - Karen A Spencer
- School of Psychology & Neuroscience, University of St Andrews, St Andrews, UK
| | - Gillian R Brown
- School of Psychology & Neuroscience, University of St Andrews, St Andrews, UK
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Gubert C, Hannan AJ. Environmental enrichment as an experience-dependent modulator of social plasticity and cognition. Brain Res 2019; 1717:1-14. [DOI: 10.1016/j.brainres.2019.03.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/11/2019] [Accepted: 03/27/2019] [Indexed: 12/14/2022]
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Candemir E, Post A, Dischinger US, Palme R, Slattery DA, O'Leary A, Reif A. Limited effects of early life manipulations on sex-specific gene expression and behavior in adulthood. Behav Brain Res 2019; 369:111927. [PMID: 31034851 DOI: 10.1016/j.bbr.2019.111927] [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: 11/29/2018] [Revised: 04/23/2019] [Accepted: 04/25/2019] [Indexed: 01/19/2023]
Abstract
Exposure to childhood adversity is associated with increased vulnerability to stress-related disorders in adulthood which has been replicated in rodent stress models, whereas environmental enrichment has been suggested to have beneficial effects. However, the exact neurobiological mechanisms underlying these environment influences on adult brain and behavior are not well understood. Therefore, we investigated the long-term effects of maternal separation (MS) or environmental enrichment (EE) in male and female CD1 mice. We found clear sex-specific effects, but limited influence of environmental manipulations, on adult behavior, fecal corticosterone metabolite (FCM) levels and stress- and plasticity related gene expression in discrete brain regions. In detail, adult females displayed higher locomotor activity and FCM levels compared to males and EE resulted in attenuation in both measures, but only in females. There were no sex- or postnatal manipulation-dependent differences in anxiety-related behaviors in either sex. Gene expression analyses revealed that adult males showed higher Fkbp5 mRNA levels in hippocampus, hypothalamus and raphe nuclei, and higher hippocampal Nos1 levels. Interestingly, MS elevated Nos1 levels in hippocampus but reduced Fkbp5 expression in hypothalamus of males. Finally, we also found higher Maoa expression in the hypothalamus of adult females, however no differences were observed in the expression levels of Bdnf, Crhr1, Nr3c1 and Htr1a. Our findings further contribute to sex-dependent differences in behavior, corticosterone and gene expression and reveal that the effects of postnatal manipulations on these parameters in outbred CD1 mice are limited.
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Affiliation(s)
- Esin Candemir
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Antonia Post
- Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital of Würzburg, Germany
| | - Ulrich Severin Dischinger
- Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital of Würzburg, Germany
| | - Rupert Palme
- Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - David A Slattery
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany
| | - Aet O'Leary
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany; Department of Neuropsychopharmacology, Institute of Psychology, University of Tartu, Tartu, Estonia
| | - Andreas Reif
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Frankfurt am Main, Germany.
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Arroyo L, Valent D, Carreras R, Peña R, Sabrià J, Velarde A, Bassols A. Housing and road transport modify the brain neurotransmitter systems of pigs: Do pigs raised in different conditions cope differently with unknown environments? PLoS One 2019; 14:e0210406. [PMID: 30650149 PMCID: PMC6334955 DOI: 10.1371/journal.pone.0210406] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/06/2018] [Indexed: 12/23/2022] Open
Abstract
How housing and transport conditions may affect welfare in porcine production is a leading topic in livestock research. This study investigated whether pigs present a different neurological response to management conditions and to ascertain whether pigs living partially outdoors cope differently with road transport-associated stress. Twenty-four female pigs were divided in two groups: one living indoors (ID, n = 12) and the other housed combining indoor conditions with 4 hours per day of outdoor pasture (OD, n = 12). After one month, one set of animals from each housing condition were driven in a truck to the slaughterhouse in low-stress conditions (5 min drive, no mixing groups, soft management, LS group, n = 12) or high-stress conditions (2 hours drive, mixing groups, harsh management, HS group, n = 12). At the slaughterhouse, blood was collected, and the prefrontal cortex (PFC) and the hippocampus (HC) dissected. OD pigs had lower serum haptoglobin and increased dopaminergic pathway (DA-system) in the PFC, suggesting that living outdoors increases their wellbeing. HS conditions increased serum creatine kinase (CK) and affected several brain pathways: activation of the noradrenergic (NA-system) and DA -system in the PFC and the activation of the DA-system and an increase in c-Fos as well as a decrease in brain-derived neurotrophic factor (BDNF) in the HC. The serotonergic system (5-HT-system) was mildly altered in both areas. There was an interaction between housing and transport in serum NA and the DA-system in the HC, indicating that living conditions affected the response to stress. Multivariate analysis was able to discriminate the four animal groups. In conclusion, this work indicates that housing conditions and road transport markedly modifies the neurophysiology of pigs, and suggests that animals raised partially outdoors respond differently to transport-associated stress than animals raised indoors, indicating that they cope differently with unknown environments.
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Affiliation(s)
- Laura Arroyo
- Departament de Bioquímica i Biologia Molecular, Facultat de Veterinària, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Daniel Valent
- Departament de Bioquímica i Biologia Molecular, Facultat de Veterinària, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Ricard Carreras
- IRTA, Animal Welfare Subprogram, Veïnat de Sies, s/n, Monells, Spain
| | - Raquel Peña
- Departament de Bioquímica i Biologia Molecular, Facultat de Veterinària, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- Servei de Bioquímica Clínica Veterinària, Facultat de Veterinària, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Josefa Sabrià
- Departament de Bioquímica i Biologia Molecular, Facultat de Medicina, Institut de Neurociències, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Antonio Velarde
- IRTA, Animal Welfare Subprogram, Veïnat de Sies, s/n, Monells, Spain
| | - Anna Bassols
- Departament de Bioquímica i Biologia Molecular, Facultat de Veterinària, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- * E-mail:
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Kokras N, Sotiropoulos I, Besinis D, Tzouveka EL, Almeida OFX, Sousa N, Dalla C. Neuroplasticity-related correlates of environmental enrichment combined with physical activity differ between the sexes. Eur Neuropsychopharmacol 2019; 29:1-15. [PMID: 30497839 DOI: 10.1016/j.euroneuro.2018.11.1107] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 11/01/2018] [Accepted: 11/09/2018] [Indexed: 01/08/2023]
Abstract
Environmental enrichment (EE), comprising positive physical (exercise) and cognitive stimuli, influences neuronal structure and usually improves brain function. The promise of EE as a preventative strategy against neuropsychiatric disease is especially high during early postnatal development when the brain is still amenable to reorganization. Despite the fact that male and female brains differ in terms of connectivity and function that may reflect early life experiences, knowledge of the neural substrates and mechanisms by which such changes arise remains limited. This study compared the impact of EE combined with physical activity on neuroplasticity and its functional consequences in adult male and female rats; EE was provided during the first 3 months of life and our analysis focused on the hippocampus, an area implicated in cognitive behavior as well as the neuroendocrine response to stress. Both male and female rats reared in EE displayed better object recognition memory than their control counterparts. Interestingly, sex differences were revealed in the effects of EE on time spent exploring the objects during this test. Independently of sex, EE increased hippocampal turnover rates of dopamine and serotonin and reduced expression of 5-HT1A receptors; in addition, EE upregulated expression of synaptophysin, a presynaptic protein, in the hippocampus. As compared to their respective controls, EE-exposed males exhibited parallel increases in phosphorylated Tau and the GluN2B receptor, whereas females responded to EE with reduced hippocampal levels of glutamate and GluN2B. Together, these observations provide further evidence on the differential effects of EE on markers of hippocampal neuroplasticity in males and females.
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Affiliation(s)
- N Kokras
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece; First Department of Psychiatry, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - I Sotiropoulos
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal; ICVS/3B's, PT Government Associate Laboratory, Braga, Portugal; Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece
| | - D Besinis
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece
| | - E L Tzouveka
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece
| | | | - N Sousa
- Life and Health Sciences Research Institute (ICVS), University of Minho, Braga, Portugal; ICVS/3B's, PT Government Associate Laboratory, Braga, Portugal
| | - C Dalla
- Department of Pharmacology, Medical School, National and Kapodistrian University of Athens, Mikras Asias 75, Athens 11527, Greece.
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Cutuli D, Berretta E, Laricchiuta D, Caporali P, Gelfo F, Petrosini L. Pre-reproductive Parental Enriching Experiences Influence Progeny's Developmental Trajectories. Front Behav Neurosci 2018; 12:254. [PMID: 30483072 PMCID: PMC6240645 DOI: 10.3389/fnbeh.2018.00254] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 10/10/2018] [Indexed: 01/09/2023] Open
Abstract
While the positive effects of environmental enrichment (EE) applied after weaning, in adulthood, during aging, or even in the presence of brain damage have been widely described, the transgenerational effects of pre-reproductive EE have been less examined. And yet, this issue is remarkable given that parental environmental experience may imprint offspring’s phenotype over generations through many epigenetic processes. Interactions between individual and environment take place lifelong even before conception. In fact, the environment pre-reproductively experienced by the mother and/or the father exerts a substantial impact on neural development and motor and cognitive performances of the offspring, even if not directly exposed to social, cognitive, physical and/or motor enrichment. Furthermore, pre-reproductive parental enrichment exerts a transgenerational impact on coping response to stress as well as on the social behavior of the offspring. Among the effects of pre-reproductive parental EE, a potentiation of the maternal care and a decrease in global methylation levels in the frontal cortex and hippocampus of the progeny have been described. Finally, pre-reproductive EE modifies different pathways of neuromodulation in the brain of the offspring (involving brain-derived neurotrophic factor, oxytocin and glucocorticoid receptors). The present review highlights the importance of pre-reproductive parental enrichment in altering the performances not only of animals directly experiencing it, but also of their progeny, thus opening the way to new hypotheses on the inheritance mechanisms of behavioral traits.
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Affiliation(s)
- Debora Cutuli
- Department of Psychology, Faculty of Medicine and Psychology, Sapienza University of Rome, Rome, Italy.,Fondazione Santa Lucia, Rome, Italy
| | - Erica Berretta
- Department of Psychology, Faculty of Medicine and Psychology, Sapienza University of Rome, Rome, Italy.,Fondazione Santa Lucia, Rome, Italy
| | - Daniela Laricchiuta
- Department of Psychology, Faculty of Medicine and Psychology, Sapienza University of Rome, Rome, Italy.,Fondazione Santa Lucia, Rome, Italy
| | - Paola Caporali
- Department of Psychology, Faculty of Medicine and Psychology, Sapienza University of Rome, Rome, Italy.,Fondazione Santa Lucia, Rome, Italy
| | - Francesca Gelfo
- Fondazione Santa Lucia, Rome, Italy.,Department of Human Sciences, Guglielmo Marconi University, Rome, Italy
| | - Laura Petrosini
- Department of Psychology, Faculty of Medicine and Psychology, Sapienza University of Rome, Rome, Italy.,Fondazione Santa Lucia, Rome, Italy
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Barker TH, Kind KL, Groves PD, Howarth GS, Whittaker AL. Oestrous phase cyclicity influences judgment biasing in rats. Behav Processes 2018; 157:678-684. [PMID: 29653156 DOI: 10.1016/j.beproc.2018.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 11/19/2022]
Abstract
The identification of cognitive bias has become an important measure of animal welfare. Negative cognitive biases develop from a tendency for animals to process novel information pessimistically. Judgment-bias testing is the commonplace methodology to detect cognitive biases. However, concerns with these methods have been frequently-reported; one of which being the discrepancy between male and female cognitive expression. The current study assessed the factors of social status and oestrus, to investigate whether oestrous cycle rotation, or subordination stress encouraged an increase in pessimistic responses. Female Sprague-Dawley rats (n = 24) were trained on an active-choice judgment bias paradigm. Responses to the ambiguous probe were recorded as optimistic or pessimistic. Oestrous phase was determined by assessing vaginal cytology in stained vaginal cell smears. Rats in the dioestrous phase and those rats considered to be subordinate demonstrated an increased percentage of pessimistic responses. However, no interaction between these factors was observed. This suggests that oestrous cyclicity can influence the judgment biases of female animals; a previously unreported finding. On this basis, researchers should be encouraged to account for both oestrous phase cyclicity and social status as an additional fixed effect in study design.
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Affiliation(s)
- Timothy Hugh Barker
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, Australia.
| | - Karen Lee Kind
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, Australia
| | - Peta Danielle Groves
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, Australia
| | - Gordon Stanley Howarth
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, Australia; Gastroenterology Department, Children, Youth and Women's Health Service, Adelaide, South Australia, Australia
| | - Alexandra Louise Whittaker
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, Australia
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Amygdala - and serum - neurotrophic factor levels depend on rearing condition in male rats. J Dev Orig Health Dis 2018; 9:377-380. [PMID: 29582716 DOI: 10.1017/s2040174418000144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Early life experiences could determine brain and behavioral development. Neurotrophic factors are likely to mediate the effects of the experience on brain structures and function. Brain-derived neurotrophic factor (BDNF) plays a central role in psychiatric disorders. To investigate the effects of early rearing condition on the amygdala - and serum - BDNF levels, we reared male Wistar rats from weaning (postnatal days 21) to adulthood (postnatal days 119) in three different rearing conditions: (1) enriched, (2) standard and (3) isolated. We found that long-term post-weaning environmental enrichment leads to lower amygdala - and serum - BDNF levels as well as lower brain weights. Grouped rearing in standard laboratory cages enhanced body weight. Thus, early rearing condition might play a crucial role in adult healthiness by predetermining individual BDNF profiles.
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Torres-Reverón A, Rivera LL, Flores I, Appleyard CB. Environmental Manipulations as an Effective Alternative Treatment to Reduce Endometriosis Progression. Reprod Sci 2017; 25:1336-1348. [PMID: 29137551 DOI: 10.1177/1933719117741374] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Treatments for endometriosis include pharmacological or surgical procedures that produce significant side effects. We aimed to determine how environmental enrichment (EE) could impact the progression of endometriosis using the autotransplantation rat model. Female rats were exposed to EE (endo-EE: toys and nesting materials, 4 rats per cage, larger area enclosure) or no enrichment (endo-NE: 2 rats per cage) starting on postnatal day 21. After 8 weeks, sham surgery or surgical endometriosis was induced by suturing uterine horn tissue next to the intestinal mesentery, then allowed to progress for 60 days during which EE or NE continued. At the time of killing, we measured anxiety behaviors, collected endometriotic vesicles and uterus, and processed for quantitative real-time polymerase chain reaction for corticotropin-releasing hormone (CRH), urocortin-1, CRH receptors type 1 and type 2, and glucocorticoid receptor (GR). Endometriosis did not affect anxiety-like behaviors, yet rats in enriched conditions showed lower basal anxiety behaviors than the nonenriched group. Importantly, the endo-EE group showed a 28% reduction in the number of endometriosis vesicles and the vesicles were significantly smaller compared to the endo-NE group. Endometriosis increased CRH and GR only in the vesicles of endo-NE, and this increase was dampened in the endo-EE. However, urocortin 1 was increased in the vesicles of the endo-EE group, suggesting different pathways of activation of CRH receptors in this group. Our results suggest that the use of multimodal complementary therapies that reduce stress in endometriosis could be an effective and safe treatment alternative, with minimal side effects.
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Affiliation(s)
- Annelyn Torres-Reverón
- 1 Division of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico.,2 Department of Biomedical Sciences, Division of Neuroscience, School of Medicine, University of Texas at Rio Grande Valley, Edinburg, TX, USA.,3 Department of Psychiatry and Neurology, School of Medicine, University of Texas at Rio Grande Valley, Edinburg, TX, USA
| | - Leslie L Rivera
- 2 Department of Biomedical Sciences, Division of Neuroscience, School of Medicine, University of Texas at Rio Grande Valley, Edinburg, TX, USA.,3 Department of Psychiatry and Neurology, School of Medicine, University of Texas at Rio Grande Valley, Edinburg, TX, USA
| | - Idhaliz Flores
- 1 Division of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico.,4 Department of Obstetrics and Gynecology, School of Medicine, Ponce Health Sciences University, Ponce, Puerto Rico
| | - Caroline B Appleyard
- 1 Division of Basic Sciences, Ponce Research Institute, Ponce Health Sciences University, Ponce, Puerto Rico.,5 Department of Internal Medicine, School of Medicine, Ponce Health Sciences University, Ponce, Puerto Rico
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Light color importance for circadian entrainment in a diurnal (Octodon degus) and a nocturnal (Rattus norvegicus) rodent. Sci Rep 2017; 7:8846. [PMID: 28821732 PMCID: PMC5562902 DOI: 10.1038/s41598-017-08691-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 07/12/2017] [Indexed: 02/06/2023] Open
Abstract
The central circadian pacemaker (Suprachiasmatic Nuclei, SCN) maintains the phase relationship with the external world thanks to the light/dark cycle. Light intensity, spectra, and timing are important for SCN synchronisation. Exposure to blue-light at night leads to circadian misalignment that could be avoided by using less circadian-disruptive wavelengths. This study tests the capacity of a diurnal Octodon degus and nocturnal Rattus norvegicus to synchronise to different nocturnal lights. Animals were subjected to combined red-green-blue lights (RGB) during the day and to: darkness; red light (R); combined red-green LED (RG) lights; and combined red-green-violet LED (RGV) lights during the night. Activity rhythms free-ran in rats under a RGB:RG cycle and became arrhythmic under RGB:RGV. Degus remained synchronised, despite the fact that day and night-time lighting systems differed only in spectra, but not in intensity. For degus SCN c-Fos activation by light was stronger with RGB-light than with RGV. This could be relevant for developing lighting that reduces the disruptive effects of nocturnal light in humans, without compromising chromaticity.
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Colomina MT, Peris-Sampedro F. Aluminum and Alzheimer’s Disease. ADVANCES IN NEUROBIOLOGY 2017; 18:183-197. [DOI: 10.1007/978-3-319-60189-2_9] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Sex differences in performance on a cognitive bias task in Norway rats. Behav Processes 2016; 133:52-55. [PMID: 27836736 DOI: 10.1016/j.beproc.2016.11.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 11/02/2016] [Accepted: 11/06/2016] [Indexed: 11/23/2022]
Abstract
Cognitive biases, which are defined as distortions in cognitive processes that are influenced by a background emotional state, can provide information about an individual's affective state. For instance, negative cognitive biases, where individuals assess ambiguous situations as unrewarding, are commonly found in humans suffering from anxiety disorders. Cognitive biases are also increasingly used as indicators of affective state in animals. As it is not clear whether female and male animals differ in performance on cognitive bias tasks, we used a spatial location task to examine cognitive bias in female and male adult Norway rats (Rattus norvegicus). We trained the rats to distinguish between reward and unrewarded locations, and then provided food pots at ambiguous, intermediate positions. We found that, during testing, females were slowest to approach the unrewarded location, while they approached ambiguous and rewarded locations similarly quickly. In contrast, the males approached all locations quickly. This sex difference is consistent with previous evidence that male rats are quicker than females to extinguish previously learned associations. Cognitive bias tasks could therefore be used to examine sex differences in learning strategies, as well as providing opportunities to test predictions about sex differences in welfare requirements.
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Hendershott TR, Cronin ME, Langella S, McGuinness PS, Basu AC. Effects of environmental enrichment on anxiety-like behavior, sociability, sensory gating, and spatial learning in male and female C57BL/6J mice. Behav Brain Res 2016; 314:215-25. [PMID: 27498148 DOI: 10.1016/j.bbr.2016.08.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 07/29/2016] [Accepted: 08/02/2016] [Indexed: 12/29/2022]
Abstract
The influence of housing on cognition and emotional regulation in mice presents a problem for the study of genetic and environmental risk factors for neuropsychiatric disorders: standard laboratory housing may result in low levels of cognitive function or altered levels of anxiety that leave little room for assessment of deleterious effects of experimental manipulations. The use of enriched environment (EE) may allow for the measurement of a wider range of performance in cognitive domains. Cognitive and behavioral effects of EE in male mice have not been widely reproduced, perhaps due to variability in the application of enrichment protocols, and the effects of EE in female mice have not been widely studied. We have developed an EE protocol using common laboratory equipment that, without a running wheel for exercise, results in significant cognitive and behavioral effects relative to standard laboratory housing conditions. We compared male and female wild-type C57BL/6J mice reared from weaning age in an EE to those reared in a standard environment (SE), using common measures of anxiety-like behavior, sensory gating, sociability, and spatial learning and memory. Sex was a significant factor in relevant elevated plus maze (EPM) measures, and bordered on significance in a social interaction (SI) assay. Effects of EE on anxiety-like behavior and sociability were indicative of a general increase in exploratory activity. In male and female mice, EE resulted in reduced prepulse inhibition (PPI) of the acoustic startle response, and enhanced spatial learning and use of spatially precise strategies in a Morris water maze task.
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Affiliation(s)
- Taylor R Hendershott
- Department of Psychology, College of the Holy Cross, 1 College Street, Worcester, MA 01610, United States
| | - Marie E Cronin
- Department of Psychology, College of the Holy Cross, 1 College Street, Worcester, MA 01610, United States
| | - Stephanie Langella
- Department of Psychology, College of the Holy Cross, 1 College Street, Worcester, MA 01610, United States
| | - Patrick S McGuinness
- Department of Psychology, College of the Holy Cross, 1 College Street, Worcester, MA 01610, United States
| | - Alo C Basu
- Department of Psychology, College of the Holy Cross, 1 College Street, Worcester, MA 01610, United States.
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Transient Receptor Potential-canonical 1 is Essential for Environmental Enrichment-Induced Cognitive Enhancement and Neurogenesis. Mol Neurobiol 2016; 54:1992-2002. [DOI: 10.1007/s12035-016-9758-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 01/26/2016] [Indexed: 10/22/2022]
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48
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Ortiz-Pérez A, Espinosa-Raya J, Picazo O. An enriched environment and 17-beta estradiol produce similar pro-cognitive effects on ovariectomized rats. Cogn Process 2016; 17:15-25. [DOI: 10.1007/s10339-015-0746-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 12/11/2015] [Indexed: 02/01/2023]
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EEG Radiotelemetry in Small Laboratory Rodents: A Powerful State-of-the Art Approach in Neuropsychiatric, Neurodegenerative, and Epilepsy Research. Neural Plast 2015; 2016:8213878. [PMID: 26819775 PMCID: PMC4706962 DOI: 10.1155/2016/8213878] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 08/27/2015] [Indexed: 02/04/2023] Open
Abstract
EEG radiotelemetry plays an important role in the neurological characterization of transgenic mouse models of neuropsychiatric and neurodegenerative diseases as well as epilepsies providing valuable insights into underlying pathophysiological mechanisms and thereby facilitating the development of new translational approaches. We elaborate on the major advantages of nonrestraining EEG radiotelemetry in contrast to restraining procedures such as tethered systems or jacket systems containing recorders. Whereas a main disadvantage of the latter is their unphysiological, restraining character, telemetric EEG recording overcomes these disadvantages. It allows precise and highly sensitive measurement under various physiological and pathophysiological conditions. Here we present a detailed description of a straightforward successful, quick, and efficient technique for intraperitoneal as well as subcutaneous pouch implantation of a standard radiofrequency transmitter in mice and rats. We further present computerized 3D-stereotaxic placement of both epidural and deep intracerebral electrodes. Preoperative preparation of mice and rats, suitable anaesthesia, and postoperative treatment and pain management are described in detail. A special focus is on fields of application, technical and experimental pitfalls, and technical connections of commercially available radiotelemetry systems with other electrophysiological setups.
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Vega-Rivera NM, Ortiz-López L, Gómez-Sánchez A, Oikawa-Sala J, Estrada-Camarena EM, Ramírez-Rodríguez GB. The neurogenic effects of an enriched environment and its protection against the behavioral consequences of chronic mild stress persistent after enrichment cessation in six-month-old female Balb/C mice. Behav Brain Res 2015; 301:72-83. [PMID: 26721469 DOI: 10.1016/j.bbr.2015.12.028] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 12/10/2015] [Accepted: 12/16/2015] [Indexed: 01/02/2023]
Abstract
Because stress may underlie the presence of depressive episodes, strategies to produce protection against or to reverse the effects of stress on neuroplasticity and behavior are relevant. Preclinical studies showed that exposure to stimuli, such as physical activity and environmental enrichment (ENR), produce beneficial effects against stress causing antidepressant-like effects in rodents. Additionally, ENR induces positive effects on neuroplasticity, neurochemistry and behavior at any age of rodents tested. Here, we analyzed whether ENR exposure prevents the development of depressive-like behavior produced by unpredictable, chronic mild stress (CMS) exposure as well as changes in hippocampal neurogenesis in a six-month-old female Balb/C mice, strain that shows low baseline levels of hippocampal neurogenesis. Mice were assigned to one of four groups: (1) normal housing-normal housing (NH-NH), (2) NH-CMS, (3) ENR-NH, or (4) ENR-CMS. The animals were exposed over 46 days to ENR or NH and subsequently to NH or CMS for 4 weeks. ENR induces long-term effects protecting against CMS induction of anhedonia and hopelessness behaviors. Independent of housing conditions, ENR increased the number of proliferative cells (Ki67), and CMS decreased the number of proliferative cells. ENR increased the newborn cells (BrdU) and mature phenotypes of neurons; these effects were not changed by CMS exposure. Similarly, the number of doublecortin-positive cells was not affected by CMS in ENR mice, which showed more cells with complex dendrite arborizations. Our study suggests that ENR induces protection against the effects of CMS on behavior and neuroplasticity in six-month-old Balb/C mice.
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Affiliation(s)
- Nelly Maritza Vega-Rivera
- Laboratory of Neuropsychopharmacology, Division of Neurosciences, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calz. México-Xochimilco 101, 14370 México, D.F., Mexico
| | - Leonardo Ortiz-López
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calzada México-Xochimilco 101, 14370 México, D.F., Mexico
| | - Ariadna Gómez-Sánchez
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calzada México-Xochimilco 101, 14370 México, D.F., Mexico
| | - Julian Oikawa-Sala
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calzada México-Xochimilco 101, 14370 México, D.F., Mexico
| | - Erika Monserrat Estrada-Camarena
- Laboratory of Neuropsychopharmacology, Division of Neurosciences, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calz. México-Xochimilco 101, 14370 México, D.F., Mexico.
| | - Gerardo Bernabé Ramírez-Rodríguez
- Laboratory of Neurogenesis, Division of Clinical Investigations, National Institute of Psychiatry "Ramón de la Fuente Muñiz", Calzada México-Xochimilco 101, 14370 México, D.F., Mexico.
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