1
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Jia P, Wang J, Ren X, He J, Wang S, Xing Y, Chen D, Zhang X, Zhou S, Liu X, Yu S, Li Z, Jiang C, Zang W, Chen X, Wang J. An enriched environment improves long-term functional outcomes in mice after intracerebral hemorrhage by mechanisms that involve the Nrf2/BDNF/glutaminase pathway. J Cereb Blood Flow Metab 2023; 43:694-711. [PMID: 36635875 PMCID: PMC10108193 DOI: 10.1177/0271678x221135419] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 01/14/2023]
Abstract
Post-stroke depression exacerbates neurologic deficits and quality of life. Depression after ischemic stroke is known to some extent. However, depression after intracerebral hemorrhage (ICH) is relatively unknown. Increasing evidence shows that exposure to an enriched environment (EE) after cerebral ischemia/reperfusion injury has neuroprotective effects in animal models, but its impact after ICH is unknown. In this study, we investigated the effect of EE on long-term functional outcomes in mice subjected to collagenase-induced striatal ICH. Mice were subjected to ICH with the standard environment (SE) or ICH with EE for 6 h/day (8:00 am-2:00 pm). Depressive, anxiety-like behaviors and cognitive tests were evaluated on day 28 with the sucrose preference test, tail suspension test, forced swim test, light-dark transition experiment, morris water maze, and novel object recognition test. Exposure to EE improved neurologic function, attenuated depressive and anxiety-like behaviors, and promoted spatial learning and memory. These changes were associated with increased expression of transcription factor Nrf2 and brain-derived neurotrophic factor (BDNF) and inhibited glutaminase activity in the perihematomal tissue. However, EE did not change the above behavioral outcomes in Nrf2-/- mice on day 28. Furthermore, exposure to EE did not increase BDNF expression compared to exposure to SE in Nrf2-/- mice on day 28 after ICH. These findings indicate that EE improves long-term outcomes in sensorimotor, emotional, and cognitive behavior after ICH and that the underlying mechanism involves the Nrf2/BDNF/glutaminase pathway.
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Affiliation(s)
- Peijun Jia
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
- School of Life Sciences,
Zhengzhou University, Zhengzhou, China
| | - Junmin Wang
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Xiuhua Ren
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Jinxin He
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Shaoshuai Wang
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Yinpei Xing
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Danyang Chen
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Xinling Zhang
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Siqi Zhou
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Xi Liu
- Department of Neurology,
The First Affiliated Hospital of Zhengzhou University, Zhengzhou,
China
| | - Shangchen Yu
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Zefu Li
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Chao Jiang
- Department of Neurology,
The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou,
China
| | - Weidong Zang
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Xuemei Chen
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
| | - Jian Wang
- Department of Anatomy,
School of Basic Medical Sciences, , Zhengzhou
University, Zhengzhou, China
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2
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Influence of sex, age and diabetes on brain transcriptome and proteome modifications following cerebral ischemia. BMC Neurosci 2023; 24:7. [PMID: 36707762 PMCID: PMC9881265 DOI: 10.1186/s12868-023-00775-7] [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: 09/06/2022] [Accepted: 01/10/2023] [Indexed: 01/28/2023] Open
Abstract
Ischemic stroke is a major cause of death and disability worldwide. Translation into the clinical setting of neuroprotective agents showing promising results in pre-clinical studies has systematically failed. One possible explanation is that the animal models used to test neuroprotectants do not properly represent the population affected by stroke, as most of the pre-clinical studies are performed in healthy young male mice. Therefore, we aimed to determine if the response to cerebral ischemia differed depending on age, sex and the presence of comorbidities. Thus, we explored proteomic and transcriptomic changes triggered during the hyperacute phase of cerebral ischemia (by transient intraluminal middle cerebral artery occlusion) in the brain of: (1) young male mice, (2) young female mice, (3) aged male mice and (4) diabetic young male mice. Moreover, we compared each group's proteomic and transcriptomic changes using an integrative enrichment pathways analysis to disclose key common and exclusive altered proteins, genes and pathways in the first stages of the disease. We found 61 differentially expressed genes (DEG) in male mice, 77 in females, 699 in diabetics and 24 in aged mice. Of these, only 14 were commonly dysregulated in all groups. The enrichment pathways analysis revealed that the inflammatory response was the biological process with more DEG in all groups, followed by hemopoiesis. Our findings indicate that the response to cerebral ischemia regarding proteomic and transcriptomic changes differs depending on sex, age and comorbidities, highlighting the importance of incorporating animals with different phenotypes in future stroke research studies.
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3
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Yuan R, Yisen Z, Xiu W, Wei T, Wei W. Effects of enriched environment on the expression of β-amyloid and transport-related proteins LRP1 and RAGE in chronic sleep-deprived mice. Transl Neurosci 2023; 14:20220301. [PMID: 37692085 PMCID: PMC10487385 DOI: 10.1515/tnsci-2022-0301] [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: 04/09/2023] [Revised: 07/11/2023] [Accepted: 07/19/2023] [Indexed: 09/12/2023] Open
Abstract
Sleep plays an important role in the learning process and memory consolidation, and sleep deprivation (SD) leads to inadequate memory consolidation and plays an important role in brain development and plasticity. SD increases β-amyloid levels while impairing cognitive function. We explored the effect of enriched environment (EE) on β-amyloid and transporter protein LRP1 and receptor for advanced glycosylation end-products (RAGE) expression in chronic sleep deprived mice. We randomly divided mice into four groups (n = 10), the standard environment group (Ctrl group), the sleep deprivation group (SD group), the enriched environment intervention group (EE group), and the sleep deprivation plus environmental enrichment intervention group (SD + EE group). A modified multi-platform SD model was used to sleep deprive the mice for 19 h per day. Five hours of EE intervention was performed daily in the EE group and the SD + EE group, respectively. The behavioral measurements of mice were performed by Y-maze method and new object recognition; the expression levels of Aβ1-42, LRP1, and RAGE in prefrontal cortex and hippocampus of mice were measured by immunofluorescence; the expression levels of LRP1 and RAGE in prefrontal cortex and hippocampus were detected by Western blot. The results showed that EE could effectively ameliorate the effects of SD on cognitive impairment, reduce SD induced Aβ deposition, and decrease the expression of RAGE, while increase the expression of LRP1.
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Affiliation(s)
- Ren Yuan
- Department of Neurology, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning Province, China
| | - Zhang Yisen
- Department of Neurology, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning Province, China
| | - Wang Xiu
- Department of Clinical Laboratory, Wuhan Children’s Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology, Hubei Province, China
| | - Tang Wei
- Department of Neurology, Affiliated Xinhua Hospital of Dalian University, Dalian, Liaoning Province, China
| | - Wang Wei
- Department of Basic Medicine, School of Medicine of Dalian University, Dalian, Liaoning Province, China
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4
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Han Y, Yuan M, Guo YS, Shen XY, Gao ZK, Bi X. The role of enriched environment in neural development and repair. Front Cell Neurosci 2022; 16:890666. [PMID: 35936498 PMCID: PMC9350910 DOI: 10.3389/fncel.2022.890666] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 06/29/2022] [Indexed: 12/01/2022] Open
Abstract
In addition to genetic information, environmental factors play an important role in the structure and function of nervous system and the occurrence and development of some nervous system diseases. Enriched environment (EE) can not only promote normal neural development through enhancing neuroplasticity but also play a nerve repair role in restoring functional activities during CNS injury by morphological and cellular and molecular adaptations in the brain. Different stages of development after birth respond to the environment to varying degrees. Therefore, we systematically review the pro-developmental and anti-stress value of EE during pregnancy, pre-weaning, and “adolescence” and analyze the difference in the effects of EE and its sub-components, especially with physical exercise. In our exploration of potential mechanisms that promote neurodevelopment, we have found that not all sub-components exert maximum value throughout the developmental phase, such as animals that do not respond to physical activity before weaning, and that EE is not superior to its sub-components in all respects. EE affects the developing and adult brain, resulting in some neuroplastic changes in the microscopic and macroscopic anatomy, finally contributing to enhanced learning and memory capacity. These positive promoting influences are particularly prominent regarding neural repair after neurobiological disorders. Taking cerebral ischemia as an example, we analyzed the molecular mediators of EE promoting repair from various dimensions. We found that EE does not always lead to positive effects on nerve repair, such as infarct size. In view of the classic issues such as standardization and relativity of EE have been thoroughly discussed, we finally focus on analyzing the essentiality of the time window of EE action and clinical translation in order to devote to the future research direction of EE and rapid and reasonable clinical application.
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Affiliation(s)
- Yu Han
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Mei Yuan
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Yi-Sha Guo
- Department of Sport Rehabilitation, Shanghai University of Sport, Shanghai, China
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
| | - Xin-Ya Shen
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
- Department of Graduate School, Shanghai University of Medicine and Health Sciences Affiliated Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Zhen-Kun Gao
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
- Department of Graduate School, Shanghai University of Medicine and Health Sciences Affiliated Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Xia Bi
- Department of Rehabilitation Medicine, Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
- *Correspondence: Xia Bi
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Liu J, Zheng J, Xu Y, Cao W, Wang J, Wang B, Zhao L, Zhang X, Liao W. Enriched Environment Attenuates Pyroptosis to Improve Functional Recovery After Cerebral Ischemia/Reperfusion Injury. Front Aging Neurosci 2021; 13:717644. [PMID: 34646128 PMCID: PMC8504677 DOI: 10.3389/fnagi.2021.717644] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/01/2021] [Indexed: 12/16/2022] Open
Abstract
Enriched environment (EE) is a complex containing social, cognitive, and motor stimuli. Exposure to EE can promote functional recovery after ischemia/reperfusion (I/R) injury. However, the underlying mechanisms remained unclear. Pyroptosis has recently been identified and demonstrated a significant role in ischemic stroke. The purpose of this study was to explore the effect of EE on neuronal pyroptosis after cerebral I/R injury. In the current study, middle cerebral artery occlusion/reperfusion (MCAO/R) was applied to establish the cerebral I/R injury model. Behavior tests including the modified Neurological Severity Scores (mNSS) and the Morris Water Maze (MWM) were performed. The infarct volume was evaluated by Nissl staining. To evaluate the levels of pyroptosis-related proteins, the levels of GSDMD-N and nod-like receptor protein 1/3 (NLRP1/3) inflammasome-related proteins were examined. The mRNA levels of IL-1β and IL-18 were detected by Quantitative Real-Time PCR (qPCR). The secretion levels of IL-1β and IL-18 were analyzed by ELISA. Also, the expression of p65 and p-p65 were detected. The results showed that EE treatment improved functional recovery, reduced infarct volume, attenuated neuronal pyroptosis after cerebral I/R injury. EE treatment also suppressed the activities of NLRP1/NLRP3 inflammasomes. These may be affected by inhabiting the NF-κB p65 signaling pathway. Our findings suggested that neuronal pyroptosis was probably the neuroprotective mechanism that EE treatment rescued neurological deficits after I/R injury.
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Affiliation(s)
- Jingying Liu
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jun Zheng
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yang Xu
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, China
| | - Wenyue Cao
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Jinchen Wang
- Department of Anesthesiology, Zhujiang Hospital of Southern Medical University, Guangzhou, China
| | - Biru Wang
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Linyao Zhao
- Department of Neurosurgery, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xin Zhang
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Weijing Liao
- Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
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Ceanga M, Dahab M, Witte OW, Keiner S. Adult Neurogenesis and Stroke: A Tale of Two Neurogenic Niches. Front Neurosci 2021; 15:700297. [PMID: 34447293 PMCID: PMC8382802 DOI: 10.3389/fnins.2021.700297] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Accepted: 06/30/2021] [Indexed: 01/17/2023] Open
Abstract
In the aftermath of an acute stroke, numerous signaling cascades that reshape the brain both in the perilesional zone as well as in more distal regions are activated. Despite continuous improvement in the acute treatment of stroke and the sustained research efforts into the pathophysiology of stroke, we critically lag in our integrated understanding of the delayed and chronic responses to ischemic injury. As such, the beneficial or maladaptive effect of some stroke-induced cellular responses is unclear, restricting the advancement of therapeutic strategies to target long-term complications. A prominent delayed effect of stroke is the robust increase in adult neurogenesis, which raises hopes for a regenerative strategy to counter neurological deficits in stroke survivors. In the adult brain, two regions are known to generate new neurons from endogenous stem cells: the subventricular zone (SVZ) and the dentate subgranular zone (SGZ) of the hippocampus. While both niches respond with an increase in neurogenesis post-stroke, there are significant regional differences in the ensuing stages of survival, migration, and maturation, which may differently influence functional outcome. External interventions such as rehabilitative training add a further layer of complexity by independently modulating the process of adult neurogenesis. In this review we summarize the current knowledge regarding the effects of ischemic stroke on neurogenesis in the SVZ and in the SGZ, and the influence of exogenous stimuli such as motor activity or enriched environment (EE). In addition, we discuss the contribution of SVZ or SGZ post-stroke neurogenesis to sensory, motor and cognitive recovery.
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Affiliation(s)
- Mihai Ceanga
- Hans-Berger Department of Neurology, Jena University Hospital, Jena, Germany.,Section Translational Neuroimmunology, Department of Neurology, Jena University Hospital, Jena, Germany
| | - Mahmoud Dahab
- Hans-Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Otto W Witte
- Hans-Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Silke Keiner
- Hans-Berger Department of Neurology, Jena University Hospital, Jena, Germany
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7
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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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8
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Samandari H, Nabavizadeh F, Ashabi G. Age-related difference in protective effect of early post-conditioning on ischemic brain injury: possible involvement of MAP-2/Synaptophysin role. Metab Brain Dis 2019; 34:1771-1780. [PMID: 31471737 DOI: 10.1007/s11011-019-00484-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 08/15/2019] [Indexed: 12/16/2022]
Abstract
Brain Ischemia/Reperfusion (I/R) injury leads to the failure of the microtubules function and neuronal death. Ischemic post-conditioning is defined as a series of rapid alternating interruptions of blood flow in the first seconds of reperfusion. In the present study, the caspase-3, Microtubule-Associated Protein-2 (MAP-2), Protein Kinase C α (PKCα), c-fos, and synaptophysin were evaluated in the hippocampus of focal I/R post-conditioning model in a time -dependent study in aged and young rats. Adult and aged rats were subjected to right MCAO for 30 min and post-conditioned (10 s) for 3 cycles. Sensory-motor tests were performed, and locomotion and anxiety-like behavior were evaluated. Molecular tests were done by detection kit, RT-PCR, and Western blotting techniques. Ninety-six hours after I/R post-conditioning, neurological signs, locomotion, anxiety-like behavior, and ischemic area were improved in young rats compared to 6 h after I/R post-conditioning (P < 0.001). Caspase-3 activity declined in the hippocampus and cortex of I/R post-conditioned young rats in 96 h after I/R post-conditioning compared with 6 h after I/R post-conditioning (P < 0.001). Also, MAP-2 mRNA, MAP-2 protein level, PKCα, c-fos and synaptophysin protein levels were enhanced during post-conditioning in young rats in 96 h after I/R post-conditioning compared with 6 h after induction of I/R post-conditioning. The results of the present study suggested that, early post-conditioning might be considered as a candidate for therapeutic methods against I/R in the adult animals not aged rats. Moreover, inhibition of cell death in post-conditioned ischemic rats was found to be regulated by some neuroprotective molecules as well as MAP-2 and c-fos in young rats. Graphical abstract Graphical abstract representing the post-conditioning (PC) treatment timeline in adult and old rats.
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Affiliation(s)
- Hedayat Samandari
- Electrophysiology Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Nabavizadeh
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Ghorbangol Ashabi
- Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
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9
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The “Use It or Lose It” Dogma in the Retina: Visual Stimulation Promotes Protection Against Retinal Ischemia. Mol Neurobiol 2019; 57:435-449. [DOI: 10.1007/s12035-019-01715-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 07/18/2019] [Indexed: 01/12/2023]
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10
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Postischemic Housing Environment on Cerebral Metabolism and Neuron Apoptosis after Focal Cerebral Ischemia in Rats. Curr Med Sci 2018; 38:656-665. [DOI: 10.1007/s11596-018-1927-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 05/15/2018] [Indexed: 01/13/2023]
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11
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Zhao LR, Willing A. Enhancing endogenous capacity to repair a stroke-damaged brain: An evolving field for stroke research. Prog Neurobiol 2018; 163-164:5-26. [PMID: 29476785 PMCID: PMC6075953 DOI: 10.1016/j.pneurobio.2018.01.004] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 01/11/2018] [Accepted: 01/30/2018] [Indexed: 02/07/2023]
Abstract
Stroke represents a severe medical condition that causes stroke survivors to suffer from long-term and even lifelong disability. Over the past several decades, a vast majority of stroke research targets neuroprotection in the acute phase, while little work has been done to enhance stroke recovery at the later stage. Through reviewing current understanding of brain plasticity, stroke pathology, and emerging preclinical and clinical restorative approaches, this review aims to provide new insights to advance the research field for stroke recovery. Lifelong brain plasticity offers the long-lasting possibility to repair a stroke-damaged brain. Stroke impairs the structural and functional integrity of entire brain networks; the restorative approaches containing multi-components have great potential to maximize stroke recovery by rebuilding and normalizing the stroke-disrupted entire brain networks and brain functioning. The restorative window for stroke recovery is much longer than previously thought. The optimal time for brain repair appears to be at later stage of stroke rather than the earlier stage. It is expected that these new insights will advance our understanding of stroke recovery and assist in developing the next generation of restorative approaches for enhancing brain repair after stroke.
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Affiliation(s)
- Li-Ru Zhao
- Department of Neurosurgery, State University of New York, Upstate Medical University, Syracuse, NY, 13210, USA.
| | - Alison Willing
- Center for Excellence in Aging and Brain Repair, Department of Neurosurgery and Brain Repair, University of South Florida, Morsani College of Medicine, Tampa, FL, 33612, USA.
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12
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Wixey JA, Reinebrant HE, Chand KK, Buller KM. Disruption to the 5-HT 7 Receptor Following Hypoxia-Ischemia in the Immature Rodent Brain. Neurochem Res 2018; 43:711-720. [PMID: 29357019 DOI: 10.1007/s11064-018-2473-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/06/2018] [Accepted: 01/09/2018] [Indexed: 10/18/2022]
Abstract
It has become increasingly evident the serotonergic (5-hydroxytryptamine, 5-HT) system is an important central neuronal network disrupted following neonatal hypoxic-ischemic (HI) insults. Serotonin acts via a variety of receptor subtypes that are differentially associated with behavioural and cognitive mechanisms. The 5-HT7 receptor is purported to play a key role in epilepsy, anxiety, learning and memory and neuropsychiatric disorders. Furthermore, the 5-HT7 receptor is highly localized in brain regions damaged following neonatal HI insults. Utilising our well-established neonatal HI model in the postnatal day 3 (P3) rat pup we demonstrated a significant decrease in levels of the 5-HT7 protein in the frontal cortex, thalamus and brainstem one week after insult. We also observed a relative decrease in both the cytosolic and membrane fractions of 5-HT7. The 5-HT7 receptor was detected on neurons throughout the cortex and thalamus, and 5-HT cell bodies in the brainstem. However we found no evidence of 5-HT7 co-localisation on microglia or astrocytes. Moreover, minocycline treatment did not significantly prevent the HI-induced reductions in 5-HT7. In conclusion, neonatal HI injury caused significant disruption to 5-HT7 receptors in the forebrain and brainstem. Yet the use of minocycline to inhibit activated microglia, did not prevent the HI-induced changes in 5-HT7 expression.
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Affiliation(s)
- Julie A Wixey
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD, 4029, Australia.
| | - Hanna E Reinebrant
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD, 4029, Australia.,Mater Research Institute, The University of Queensland (MRI-UQ), Brisbane, Australia
| | - Kirat K Chand
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD, 4029, Australia
| | - Kathryn M Buller
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, QLD, 4029, Australia
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13
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Effect of Physical and Social Components of Enriched Environment on Astrocytes Proliferation in Rats After Cerebral Ischemia/Reperfusion Injury. Neurochem Res 2017; 42:1308-1316. [DOI: 10.1007/s11064-016-2172-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/26/2016] [Accepted: 12/29/2016] [Indexed: 12/27/2022]
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14
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Hasan SMM, Rancourt SN, Austin MW, Ploughman M. Defining Optimal Aerobic Exercise Parameters to Affect Complex Motor and Cognitive Outcomes after Stroke: A Systematic Review and Synthesis. Neural Plast 2016; 2016:2961573. [PMID: 26881101 PMCID: PMC4736968 DOI: 10.1155/2016/2961573] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 11/27/2015] [Accepted: 11/29/2015] [Indexed: 01/21/2023] Open
Abstract
Although poststroke aerobic exercise (AE) increases markers of neuroplasticity and protects perilesional tissue, the degree to which it enhances complex motor or cognitive outcomes is unknown. Previous research suggests that timing and dosage of exercise may be important. We synthesized data from clinical and animal studies in order to determine optimal AE training parameters and recovery outcomes for future research. Using predefined criteria, we included clinical trials of stroke of any type or duration and animal studies employing any established models of stroke. Of the 5,259 titles returned, 52 articles met our criteria, measuring the effects of AE on balance, lower extremity coordination, upper limb motor skills, learning, processing speed, memory, and executive function. We found that early-initiated low-to-moderate intensity AE improved locomotor coordination in rodents. In clinical trials, AE improved balance and lower limb coordination irrespective of intervention modality or parameter. In contrast, fine upper limb recovery was relatively resistant to AE. In terms of cognitive outcomes, poststroke AE in animals improved memory and learning, except when training was too intense. However, in clinical trials, combined training protocols more consistently improved cognition. We noted a paucity of studies examining the benefits of AE on recovery beyond cessation of the intervention.
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Affiliation(s)
- S. M. Mahmudul Hasan
- Recovery & Performance Laboratory, Faculty of Medicine, Memorial University, L.A. Miller Centre, Room 400, 100 Forest Road, St. John's, NL, Canada A1A 1E5
| | - Samantha N. Rancourt
- Recovery & Performance Laboratory, Faculty of Medicine, Memorial University, L.A. Miller Centre, Room 400, 100 Forest Road, St. John's, NL, Canada A1A 1E5
| | - Mark W. Austin
- Recovery & Performance Laboratory, Faculty of Medicine, Memorial University, L.A. Miller Centre, Room 400, 100 Forest Road, St. John's, NL, Canada A1A 1E5
| | - Michelle Ploughman
- Recovery & Performance Laboratory, Faculty of Medicine, Memorial University, L.A. Miller Centre, Room 400, 100 Forest Road, St. John's, NL, Canada A1A 1E5
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15
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Abstract
Social isolation has been recognized as a major risk factor for morbidity and mortality in humans for more than a quarter century. The brain is the key organ of social connections and processes, however, and the same objective social relationship can be experienced as caring and protective or as exploitive and isolating. We review evidence that the perception of social isolation (i.e., loneliness) impacts brain and behavior and is a risk factor for broad-based morbidity and mortality. However, the causal role of loneliness on neural mechanisms and mortality is difficult to test conclusively in humans. Mechanistic animal studies provide a lens through which to evaluate the neurological effects of a member of a social species living chronically on the social perimeter. Experimental studies show that social isolation produces significant changes in brain structures and processes in adult social animals. These effects are not uniform across the brain or across species but instead are most evident in brain regions that reflect differences in the functional demands of solitary versus social living for a particular species. The human and animal literatures have developed independently, however, and significant gaps also exist. The current review underscores the importance of integrating human and animal research to delineate the mechanisms through which social relationships impact the brain, health, and well-being.
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Affiliation(s)
- Stephanie Cacioppo
- High Performance Electrical NeuroImaging (HPEN) Laboratory of the Center for Cognitive and Social Neuroscience, and Department of Psychiatry and Behavioral Neuroscience, University of Chicago
| | - John P Capitanio
- California National Primate Research Center and Department of Psychology, University of California-Davis
| | - John T Cacioppo
- High Performance Electrical NeuroImaging (HPEN) Laboratory of the Center for Cognitive and Social Neuroscience, and Department of Psychiatry and Behavioral Neuroscience, University of Chicago
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16
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The effects of poststroke aerobic exercise on neuroplasticity: a systematic review of animal and clinical studies. Transl Stroke Res 2014; 6:13-28. [PMID: 25023134 DOI: 10.1007/s12975-014-0357-7] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/02/2014] [Accepted: 06/30/2014] [Indexed: 10/25/2022]
Abstract
Aerobic exercise may be a catalyst to promote neuroplasticity and recovery following stroke; however, the optimal methods to measure neuroplasticity and the effects of training parameters have not been fully elucidated. We conducted a systematic review and synthesis of clinical trials and studies in animal models to determine (1) the extent to which aerobic exercise influences poststroke markers of neuroplasticity, (2) the optimal parameters of exercise required to induce beneficial effects, and (3) consistent outcomes in animal models that could help inform the design of future trials. Synthesized findings show that forced exercise at moderate to high intensity increases brain-derived neurotrophic factor (BDNF), insulin-like growth factor-I (IGF-I), nerve growth factor (NGF), and synaptogenesis in multiple brain regions. Dendritic branching was most responsive to moderate rather than intense training. Disparity between clinical stroke and stroke models (timing of initiation of exercise, age, gender) and clinically viable methods to measure neuroplasticity are some of the areas that should be addressed in future research.
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17
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Austin MW, Ploughman M, Glynn L, Corbett D. Aerobic exercise effects on neuroprotection and brain repair following stroke: a systematic review and perspective. Neurosci Res 2014; 87:8-15. [PMID: 24997243 DOI: 10.1016/j.neures.2014.06.007] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 05/04/2014] [Accepted: 06/24/2014] [Indexed: 01/02/2023]
Abstract
Aerobic exercise (AE) enhances neuroplasticity and improves functional outcome in animal models of stroke, however the optimal parameters (days post-stroke, intensity, mode, and duration) to influence brain repair processes are not known. We searched PubMed, CINAHL, PsychInfo, the Cochrane Library, and the Central Register of Controlled Clinical Trials, using predefined criteria, including all years up to July 2013 (English language only). Clinical studies were included if participants had experienced an ischemic or hemorrhagic stroke. We included animal studies that utilized any method of global or focal ischemic stroke or intracerebral hemorrhage. Any intervention utilizing AE-based activity with the intention of improving cardiorespiratory fitness was included. Of the 4250 titles returned, 47 studies (all in animal models) met criteria and measured the effects of exercise on brain repair parameters (lesion volume, oxidative damage, inflammation and cell death, neurogenesis, angiogenesis and markers of stress). Our synthesized findings show that early-initiated (24-48h post-stroke) moderate forced exercise (10m/min, 5-7 days per week for about 30min) reduced lesion volume and protected perilesional tissue against oxidative damage and inflammation at least for the short term (4 weeks). The applicability and translation of experimental exercise paradigms to clinical trials are discussed.
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Affiliation(s)
- Mark W Austin
- Recovery and Performance Laboratory, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Michelle Ploughman
- Recovery and Performance Laboratory, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada.
| | - Lindsay Glynn
- Health Sciences Library, Faculty of Medicine, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Dale Corbett
- Canadian Partnership for Stroke Recovery and Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
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18
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Madinier A, Quattromani MJ, Sjölund C, Ruscher K, Wieloch T. Enriched housing enhances recovery of limb placement ability and reduces aggrecan-containing perineuronal nets in the rat somatosensory cortex after experimental stroke. PLoS One 2014; 9:e93121. [PMID: 24664200 PMCID: PMC3963994 DOI: 10.1371/journal.pone.0093121] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 02/28/2014] [Indexed: 12/23/2022] Open
Abstract
Stroke causes life long disabilities where few therapeutic options are available. Using electrical and magnetic stimulation of the brain and physical rehabilitation, recovery of brain function can be enhanced even late after stroke. Animal models support this notion, and housing rodents in an enriched environment (EE) several days after experimental stroke stimulates lost brain function by multisensory mechanisms. We studied the dynamics of functional recovery of rats with a lesion to the fore and hind limb motor areas induced by photothrombosis (PT), and with subsequent housing in either standard (STD) or EE. In this model, skilled motor function is not significantly enhanced by enriched housing, while the speed of recovery of sensori-motor function substantially improves over the 9-week study period. In particular, this stroke lesion completely obliterates the fore and hind limb placing ability when visual and whisker guidance is prevented, a deficit that persists for up to 9 weeks of recovery, but that is markedly restored within 2 weeks by enriched housing. Enriched housing after stroke also leads to a significant loss of perineuronal net (PNN) immunoreactivity; detection of aggrecan protein backbone with AB1031 antibody was decreased by 13–22%, and labelling of a glycan moiety of aggrecan with Cat-315 antibody was reduced by 25–30% in the peri-infarct area and in the somatosensory cortex, respectively. The majority of these cells are parvalbumin/GABA inhibitory interneurons that are important in sensori-information processing. We conclude that damage to the fore and hind limb motor areas provides a model of loss of limb placing response without visual guidance, a deficit also seen in more than 50% of stroke patients. This loss is amenable to recovery induced by multiple sensory stimulation and correlates with a decrease in aggrecan-containing PNNs around inhibitory interneurons. Modulating the PNN structure after ischemic damage may provide new therapies enhancing tactile/proprioceptive function after stroke.
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Affiliation(s)
- Alexandre Madinier
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Miriana Jlenia Quattromani
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Carin Sjölund
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Karsten Ruscher
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Tadeusz Wieloch
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, Lund, Sweden
- * E-mail:
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19
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Noninvasive strategies to promote functional recovery after stroke. Neural Plast 2013; 2013:854597. [PMID: 23864962 PMCID: PMC3707231 DOI: 10.1155/2013/854597] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 06/02/2013] [Indexed: 01/17/2023] Open
Abstract
Stroke is a common and disabling global health-care problem, which is the third most common cause of death and one of the main causes of acquired adult disability in many countries. Rehabilitation interventions are a major component of patient care. In the last few years, brain stimulation, mirror therapy, action observation, or mental practice with motor imagery has emerged as interesting options as add-on interventions to standard physical therapies. The neural bases for poststroke recovery rely on the concept of plasticity, namely, the ability of central nervous system cells to modify their structure and function in response to external stimuli. In this review, we will discuss recent noninvasive strategies employed to enhance functional recovery in stroke patients and we will provide an overview of neural plastic events associated with rehabilitation in preclinical models of stroke.
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20
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Xiao G, Sun T, Songming C, Cao Y. NR4A1 enhances neural survival following oxygen and glucose deprivation: an in vitro study. J Neurol Sci 2013; 330:78-84. [PMID: 23663895 DOI: 10.1016/j.jns.2013.04.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Revised: 04/04/2013] [Accepted: 04/10/2013] [Indexed: 12/11/2022]
Abstract
A worldwide epidemic of stroke is exacting a huge level of patient suffering and social cost. The ischemia damage to neural cells and the associated permanent neural function loss are central to the pathophysiology of stroke. In the current study, we were endeavored to identify NR4A1, an orphan nuclear receptor as a novel protector for neural cells in an in vitro neural ischemia model. Our results showed that oxygen and glucose deprivation (OGD) dramatically induced primary culture neural cell apoptosis and NR4A1 expression at both protein and mRNA level. Furthermore, hyperexpression or knock-down of NR4A1 significantly ameliorated or exacerbated OGD induced neural damage as manifested by decreased or increased apoptotic rates and key apoptotic protein expression respectively. As part of effort to identify the underlying mechanism, we also found that survivin is highly inducible following OGD and is required for NR4A1 action in this scenario. Our data seemed to be logical extensions of previous observations showing that NR4As are highly inducible following focal cerebral ischemia. Of note, our results also demonstrated that NR4A1 induction in this scenario may be functionally important as well and targeting NR4A1 protein can be intriguing as part of the effort to develop novel therapeutic strategies for neural protection after stroke.
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Affiliation(s)
- Guodong Xiao
- Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu Province, 215004, China
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21
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Ducruet AF, Sosunov SA, Visovatti SH, Petrovic-Djergovic D, Mack WJ, Connolly ES, Pinsky DJ. Paradoxical exacerbation of neuronal injury in reperfused stroke despite improved blood flow and reduced inflammation in early growth response-1 gene-deleted mice. Neurol Res 2011; 33:717-25. [PMID: 21756551 DOI: 10.1179/1743132810y.0000000022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
OBJECTIVES Early growth response gene-1 (Egr-1) coordinates the rapid upregulation of diverse inflammatory and coagulation-related genes following ischemia/reperfusion. Genetic deletion of Egr-1 results in attenuated post-ischemic injury in diverse tissue systems. In the present study, we utilized a murine model of transient middle cerebral artery occlusion to probe the functional effects of Egr-1 deletion following cerebral ischemia/reperfusion. METHODS The time course of Egr-1 expression was established by Northern/Western blot analysis, and immunocytochemistry localized Egr-1 to specific cell populations. Flow cytometry was then employed to characterize the ischemic cellular infiltrate of both wild-type (+/+) and Egr-1-null (-/-) mice. Next, the functional effect of Egr-1 deletion was investigated in Egr-1-deficient mice and their wild-type littermates subjected to middle cerebral artery occlusion. Infarct volumes, neurological scores, and reperfusion cerebral blood flow were compared between cohorts. RESULTS Rapid upregulation of Egr-1 was observed in the ischemic hemisphere, and localized primarily to neurons and mononuclear cells. Egr-1 deletion led to a suppression of infiltrating neutrophils and activated microglia/macrophages (P<0.001). Additionally, although Egr-1 deletion enhanced post-ischemic cerebral blood flow, Egr-1-deficient mice suffered larger infarcts (P=0.01) and demonstrated a trend towards worse neurological scores (P=0.06) than wild-type controls. DISCUSSION Despite a reduction in the proportion of infiltrating inflammatory cells/activated microglia and improvement in post-ischemic reperfusion, Egr-1-deficient animals suffer larger infarcts in our model. Therefore, cerebral Egr-1 expression may function to protect neurons despite its adverse modulatory consequences for inflammation and thrombosis.
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Affiliation(s)
- Andrew F Ducruet
- Department of Neurological Surgery, Columbia University, New York 10032, USA.
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22
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McClung JS, Rothi LJG, Nadeau SE. Ambient experience in restitutive treatment of aphasia. Front Hum Neurosci 2010; 4:183. [PMID: 21103021 PMCID: PMC2987679 DOI: 10.3389/fnhum.2010.00183] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Accepted: 09/07/2010] [Indexed: 01/23/2023] Open
Abstract
One of the greatest challenges to language rehabilitation is reconciling the fact that the same therapeutic intervention, provided to different individuals with similar types of stroke-induced aphasia, may result in divergent outcomes. In this paper, the authors reviewed existing literature to identify relevant ambient factors – those outside the control of the clinician – that may potentially influence functional language recovery in aphasia and response to treatment. The goal was to develop a clinical history-taking tool to assist clinicians in gathering information germane to each individual's unique circumstances and environment, elements that may have previously been underestimated, to provide a complete inventory of potentially potent prognostic factors. First, two of the authors, speech–language pathologists experienced in aphasia rehabilitation, identified and categorized factors that seemed likely to influence aphasia outcomes. Then, a wide range of literature was reviewed in an effort to identify factors empirically found to be potent influences on aphasia recovery. Where studies relating these factors to aphasia were not found, relevant research from allied fields that examined recovery from brain injury is reported. Moreover, some factors thought to be potentially potent have yet to be examined. Finally, the ambient factors supported by evidence were categorized as facilitators or barriers to functional improvement, and the Ambient Influences on Outcome Checklist (AOC) was developed, including only those factors shown to be potent in the recovery process. It is hoped that this checklist can be used to more broadly assess potential prognostic influences in aphasia restitution, as well as spawn further research.
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Affiliation(s)
- Jill S McClung
- Department of Communicative Disorders, Rehabilitation Science, College of Public Health and Health Professions, University of Florida Gainesville, FL, USA
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23
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Söderström I, Strand M, Ingridsson AC, Nasic S, Olsson T. 17beta-estradiol and enriched environment accelerate cognitive recovery after focal brain ischemia. Eur J Neurosci 2009; 29:1215-24. [PMID: 19302156 DOI: 10.1111/j.1460-9568.2009.06662.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cognitive impairments, including spatial memory and learning deficiencies, are common after ischemic stroke. Estrogen substitution improves cognitive functions in post-menopausal women and ovariectomized rodents, partially through induction of neuroplasticity in the hippocampal formation. Post-ischemic housing of male rats in an enriched environment (EE) improves functional outcome, without changing infarct volume. We hypothesized that 17beta-estradiol combined with an EE would accelerate cognitive recovery after focal brain ischemia in ovariectomized rats and that recovery would be related to altered expression of nerve growth factor-induced gene (NGFI)-A in the hippocampus. 17beta-estradiol or placebo pellets were implanted 6 h after transient middle cerebral artery occlusion. Two days later, rats were placed in an EE or a deprived environment (DE) for 6 weeks. At 5 weeks after middle cerebral artery occlusion, 17beta-estradiol-treated rats housed in an EE showed improvements in cognitive function (i.e. shorter latency and path in the Morris water maze task) compared with placebo-treated animals housed in an EE. Furthermore, beneficial effects on latency and path were observed when comparing EE-housed vs. DE-housed 17beta-estradiol-treated rats. When comparing 17beta-estradiol-treated EE-housed rats vs. placebo-treated DE-housed rats, pronounced effects on latency and path were observed. Infarct volumes did not differ between groups. 17beta-estradiol-treated EE-housed rats had significantly higher NGFI-A mRNA expression bilaterally in the cornu ammonis 1 region and in the ipsilateral dentate gyrus of the hippocampus, compared with placebo-treated EE-housed rats. In conclusion, 17beta-estradiol treatment combined with an EE improved recovery of cognitive function after experimental brain ischemia, putatively through the upregulation of NGFI-A in hippocampal subregions.
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Affiliation(s)
- Ingegerd Söderström
- Department of Public Health and Clinical Medicine, Medicine, Umeå University, Umeå, Sweden.
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24
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Penn PR, Rose FD, Johnson DA. Virtual enriched environments in paediatric neuropsychological rehabilitation following traumatic brain injury: Feasibility, benefits and challenges. Dev Neurorehabil 2009; 12:32-43. [PMID: 19283532 DOI: 10.1080/17518420902739365] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
A frequent consequence of traumatic brain injury (TBI) is a significant reduction in patients' cerebral activation/arousal, which clinicians agree is not conducive to optimal rehabilitation outcomes. In the context of paediatric rehabilitation, sustained periods of inactivity are particularly undesirable, as contemporary research has increasingly called into question the Kennard principle that youth inherently promotes greater neural plasticity and functional recovery following TBI. Therefore, the onus to create rehabilitation conditions most conducive to harnessing plasticity falls squarely on the shoulders of clinicians. Having noted the efficacy of environmental enrichment in promoting neural plasticity and positive functional outcomes in the animal literature, some researchers have suggested that the emerging technology of Virtual Reality (VR) could provide the means to increase patients' cerebral activation levels via the use of enriched Virtual Environments (VEs). However, 10 years on, this intuitively appealing concept has received almost no attention from researchers and clinicians alike. This paper overviews recent research on the benefits of enriched environments in the injured brain and identifies the potential and challenges associated with implementing VR-based enrichment in paediatric neuropsychological rehabilitation.
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Affiliation(s)
- P R Penn
- School of Psychology, University of East London, Stratford, London, UK.
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25
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Jadavji N, Metz G. Both pre- and post-lesion experiential therapy is beneficial in 6-hydroxydopamine dopamine-depleted female rats. Neuroscience 2009; 158:373-86. [DOI: 10.1016/j.neuroscience.2008.10.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2008] [Revised: 10/29/2008] [Accepted: 11/02/2008] [Indexed: 01/25/2023]
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26
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Early enriched housing results in partial recovery of memory deficits in female, but not in male, rats after neonatal hypoxia–ischemia. Brain Res 2008; 1218:257-66. [DOI: 10.1016/j.brainres.2008.04.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 04/03/2008] [Accepted: 04/06/2008] [Indexed: 11/22/2022]
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27
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Central mechanisms of HPA axis regulation by voluntary exercise. Neuromolecular Med 2008; 10:118-27. [PMID: 18273712 DOI: 10.1007/s12017-008-8027-0] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
Abstract
Stress exerts complex effects on the brain and periphery, dependent on the temporal profile and intensity of the stressor. The consequences of a stressful event can also be determined by other characteristics of the stressor, such as whether it is predictable and controllable. While the traditional view has focused primarily on the negative effects of stress on a variety of somatic systems, emerging data support the idea that certain forms of stress can enhance cellular function. Here we review the current literature on the hypothalamic-pituitary-adrenal (HPA) axis regulation by wheel running, a voluntary and controllable stressor with a distinct temporal profile. While running indeed activates a number of systems related to the stress response, other mechanisms exist to reduce the reactivity to this stressor, with possible crosstalk between running and other forms of stress.
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28
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Social instability blocks functional restitution following motor cortex stroke in rats. Behav Brain Res 2007; 188:219-26. [PMID: 18068823 DOI: 10.1016/j.bbr.2007.10.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2007] [Revised: 10/10/2007] [Accepted: 10/29/2007] [Indexed: 11/21/2022]
Abstract
Social interactions have previously been shown to influence stroke outcome. In the current experiment we investigated the effects of a changing social environment on anatomical and behavioral recovery following motor cortex stroke in rats. Adult rats were trained on the Whishaw single pellet reaching task prior to receiving a devascularizing stroke lesion of the motor cortex. During the post-stroke testing period half of the rats were exposed to a form of social experience that has previously been shown to stimulate synaptic plasticity in frontal cortex circuitry, whereas the remaining rats were housed in pairs, in standard cages. At the end of the experiment the brains were processed for Golgi-Cox staining and dendritic length was measured in layer V of the intact forelimb motor area, layer III of Zilles' area Cg3 and layer II/III of Zilles' area AID. Social experience was found to completely block the normal spontaneous behavioural restitution in the lesion animals. Anatomically, whereas social experience selectively increased dendritic length in AID in rats that had not undergone behavioral training or the stroke procedure, this was not seen in the lesion animals, as the lesion alone produced an increase in dendritic length in both AID and Cg3. The findings are discussed in terms of the role of social experiences, including stress, on spontaneous plasticity that occurs following unilateral motor cortex stroke, and the effectiveness of inducing synaptic plasticity to promote behavioural recovery.
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29
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Keith JR, Wu Y, Epp JR, Sutherland RJ. Fluoxetine and the dentate gyrus: memory, recovery of function, and electrophysiology. Behav Pharmacol 2007; 18:521-31. [PMID: 17762521 PMCID: PMC2668873 DOI: 10.1097/fbp.0b013e3282d28f83] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Chronic fluoxetine increases neurogenesis in the dentate gyrus (DG). In view of the widespread clinical use of fluoxetine and the well-established role of the DG in memory, surprisingly few studies have examined the effects of fluoxetine on memory and hippocampal electrophysiology. Additionally, few studies have evaluated the potential for fluoxetine to promote recovery of function after DG damage. Therefore, we studied the effects of long-term administration of fluoxetine on both spatial-reference memory and working memory, recovery of function after intrahippocampal colchicine infusions, which can destroy 50-70% of DG granule cells, and electrophysiological responses in the DG to perforant path stimulation in freely moving rats. Chronic fluoxetine did not affect matching-to-place or reference-memory performance in intact rats in the Morris water-maze task. Surprisingly, in rats with DG damage, recovery of function on both tasks was adversely affected by chronic fluoxetine. Finally, unlike an earlier study that reported fluoxetine-induced increases in hippocampal population spike amplitudes and excitatory postsynaptic potential slopes in urethane-anesthetized rats, electrophysiological measures in DG of freely moving rats were not affected by chronic fluoxetine treatment.
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Affiliation(s)
- Julian R Keith
- Department of Psychology, University of North Carolina at Wilmington, North Carolina 28403-5612, USA.
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30
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Abstract
1. In recent decades evidence has accumulated demonstrating the birth and functional integration of new neurons in specific regions of the adult mammalian brain, including the dentate gyrus of the hippocampus and the subventricular zone. 2. Studies in a variety of models have revealed genetic, environmental and pharmacological factors that regulate adult neurogenesis. The present review examines some of the molecular and cellular mechanisms that could be mediating these regulatory effects in both the normal and dysfunctional brain. 3. The dysregulation of adult neurogenesis may contribute to the pathogenesis of neurodegenerative disorders, such as Huntington's, Alzheimer's and Parkinson's disease, as well as psychiatric disorders such as depression. Recent evidence supports this idea and, furthermore, also indicates that factors promoting neurogenesis can modify the onset and progression of specific brain disorders, including Huntington's disease and depression.
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Affiliation(s)
- Helen E Grote
- University Laboratory of Physiology, University of Oxford, Oxford, United Kingdom
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31
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McOmish CE, Hannan AJ. Enviromimetics: exploring gene environment interactions to identify therapeutic targets for brain disorders. Expert Opin Ther Targets 2007; 11:899-913. [PMID: 17614759 DOI: 10.1517/14728222.11.7.899] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
There is a growing awareness of the central role played by environmental factors in many of the most debilitating neural disorders. Epidemiological studies have suggested a complex balance between genetic and environmental factors in the pathogenesis of neurological and psychiatric conditions. The use of accurate animal models, combined with experimental manipulations such as environmental enrichment, has shown that increased sensory, cognitive and motor stimulation has beneficial effects in a range of CNS disorders, including Huntington's, Alzheimer's, Parkinson's and other neurodegenerative diseases. Various studies have identified molecular, structural and functional correlates of this experience-dependent plasticity. The authors propose that the molecular systems which mediate the therapeutic effects of environmental enrichment may provide novel targets for pharmacotherapies. More specifically, they elaborate a theoretical framework for the development of 'enviromimetics', therapeutics that mimic or enhance the beneficial effects of environmental stimulation, targeted towards a wide range of nervous system disorders.
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Affiliation(s)
- Caitlin E McOmish
- Howard Florey Institute, University of Melbourne, VIC 3010, Australia
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32
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Ploughman M, Attwood Z, White N, Doré JJE, Corbett D. Endurance exercise facilitates relearning of forelimb motor skill after focal ischemia. Eur J Neurosci 2007; 25:3453-60. [PMID: 17553014 DOI: 10.1111/j.1460-9568.2007.05591.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Endurance exercise (i.e. running), by up-regulating brain-derived neurotrophic factor (BDNF) and other modulators of synaptic plasticity, improves attention and learning, both critical components of stroke rehabilitation. We hypothesized that, following middle cerebral artery occlusion in male Sprague-Dawley rats, endurance exercise would act synergistically with a challenging skilled forelimb task to facilitate motor recovery. Animals were randomly assigned to one of four rehabilitation conditions: no rehabilitation, running only, reach training only, and reach training preceded by running (run/reach training) for 5 weeks beginning 5 days after stroke. The behavioral outcome, morphological change and mRNA expression of proteins implicated in neuroplasticity (BDNF, synapsin I and microtubule-associated protein 2) were compared. Endurance exercise on a motorized running wheel, prior to reach training, enhanced recovery of skilled reaching ability but did not transfer to gross motor skills such as postural support (forelimb asymmetry test) and gait (ladder rung walking test). Microtubule-associated protein 2 staining density in the run/reach group was slightly enhanced in the contralateral motor cortex compared with the contralateral sensory and ipsilateral cingulate cortices, suggesting that running preceding reach training may have resulted in more dendritic branching within the motor cortex in this group. No significant differences in mRNA levels were detected among the training paradigms; however, there was a trend toward greater BDNF and synapsin I mRNA in the reaching groups. These findings suggest that exercise facilitates learning of subsequent challenging reaching tasks after stroke, which has the potential to optimize outcomes in patients with stroke.
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Affiliation(s)
- Michelle Ploughman
- Basic Medical Sciences, Faculty of Medicine, Memorial University, St. John's, NL, Canada A1B 3V6
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Ploughman M, Granter-Button S, Chernenko G, Attwood Z, Tucker BA, Mearow KM, Corbett D. Exercise intensity influences the temporal profile of growth factors involved in neuronal plasticity following focal ischemia. Brain Res 2007; 1150:207-16. [PMID: 17382914 DOI: 10.1016/j.brainres.2007.02.065] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 02/26/2007] [Accepted: 02/27/2007] [Indexed: 01/03/2023]
Abstract
Exercise increases brain-derived neurotrophic factor (BDNF), phosphorylated cAMP response-element binding protein (pCREB), insulin-like growth factor (IGF-I) and synapsin-I, each of which has been implicated in neuroplastic processes underlying recovery from ischemia. In this study we examined the temporal profile (0, 30, 60 and 120 min following exercise) of these proteins in the hippocampus and sensorimotor cortex following both motorized (60 min) and voluntary (12 h) running, 2 weeks after focal ischemia. Our goal was to identify the optimal training paradigms (intensity, duration and frequency) needed to integrate endurance exercise in stroke rehabilitation. Therefore we utilized telemetry to measure changes in heart rate with both exercise methods. Our findings show that although the more intense, motorized running exercise induced a rapid increase in BDNF, the elevation was more short-lived than with voluntary running. Motorized running was also associated with higher levels of synapsin-I in several brain regions but simultaneously, a more pronounced increase in the stress hormone, corticosterone. Furthermore, both forms of exercise resulted in decreased phosphorylation of CREB and downregulation of synapsin-I in hippocampus beginning 30 to 60 min after the exercise bout. This phenomenon was more robust after motorized running, the method that generated higher heart rate and serum corticosterone levels. This immediate stress response is likely specific to acute exercise and may diminish with repeated exercise exposure. The present data illustrate a complex interaction between different forms of exercise and proteins implicated in neuroplasticity. For clinical application, frequent lower intensity exercise episodes (as in voluntary running wheels), which may be safer to provide to patients with stroke, has a delayed but sustained effect on BDNF that may support brain remodeling after stroke.
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Affiliation(s)
- Michelle Ploughman
- Basic Medical Science, Faculty of Medicine, Memorial University, St. John's NL, Canada A1B 3V6
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Fischer FR, Peduzzi JD. Functional recovery in rats with chronic spinal cord injuries after exposure to an enriched environment. J Spinal Cord Med 2007; 30:147-55. [PMID: 17591227 PMCID: PMC2031947 DOI: 10.1080/10790268.2007.11753926] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2006] [Accepted: 11/04/2006] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND/OBJECTIVE The objective of this study was to determine the effect of environmental enrichment on the sensorimotor function of rats with chronic spinal cord injuries. DESIGN Adult Sprague-Dawley rats received a contusive injury of moderate severity at vertebral level T8 using a weight-drop device. Three months after injury, 1 randomized group (n = 16) of rats was placed in an enriched environment, whereas the control group (n = 16) remained housed in standard laboratory cages (2/cage). METHODS Animals were placed in an enriched environment for 4 weeks beginning at 3 months after injury. The enriched environment consisted of a large cage (5-6 rats/cage) with access to items such as tubes, ramps, and running wheel, with items changed daily. MAIN OUTCOME MEASURES Functional evaluation consisted of the open field Basso, Beattie and Bresnahan (BBB) locomotor test and the tests that form the combined behavioral score (CBS). The CBS includes motor score, toe spread, placing, withdrawal, righting, inclined plane, hot plate, and swim tests. Behavioral testing was repeated 7 times before and after the period of intervention. RESULTS The group placed in the enriched environment scored significantly better on the BBB (ANOVA repeated-measures, P < 0.01) test and CBS (ANOVA repeated-measures, P < 0.01). CONCLUSIONS Environmental enrichment results in significant functional improvement in animals with spinal cord injury even with a substantial delay in initiating treatment after injury. The features of an enriched environment that may be responsible for the improvement include social interactions, exercise, and novel items in an interesting environment. These findings suggest a continued plasticity of the chronically injured rat spinal cord and a possible therapeutic intervention for people with spinal cord injury.
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Affiliation(s)
| | - Jean D Peduzzi
- Wayne State University School of Medicine, Detroit, Michigan
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Abstract
There is a compelling need to develop cell and pharmacological therapeutic approaches to be administered beyond the hyperacute phase of stroke. These therapies capitalize on the capacity of the brain for neuroregeneration and neuroplasticity and are designed to reduce neurological deficits after stroke. This review provides an update of bone marrow-derived mesenchymal stem cells (MSCs) and select pharmacological agents in clinical use for other indications that promote the recovery process in the subacute and chronic phases after stroke. Among these agents are 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins), erythropoietin (EPO), and phosphodiesterase type 5 (PDE-5) inhibitors and nitric oxide (NO) donors. Both the MSCs and the pharmacologic agents potentiate brain plasticity and neurobehavioral recovery after stroke.
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Affiliation(s)
- Jieli Chen
- />Department of Neurology, Henry Ford Health Sciences Center, Detroit, Michigan
| | - Michael Chopp
- />Department of Neurology, Henry Ford Health Sciences Center, Detroit, Michigan
- />Department of Physics, Oakland University, Rochester, Michigan
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36
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Nithianantharajah J, Hannan AJ. Enriched environments, experience-dependent plasticity and disorders of the nervous system. Nat Rev Neurosci 2006; 7:697-709. [PMID: 16924259 DOI: 10.1038/nrn1970] [Citation(s) in RCA: 1214] [Impact Index Per Article: 67.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Behavioural, cellular and molecular studies have revealed significant effects of enriched environments on rodents and other species, and provided new insights into mechanisms of experience-dependent plasticity, including adult neurogenesis and synaptic plasticity. The demonstration that the onset and progression of Huntington's disease in transgenic mice is delayed by environmental enrichment has emphasized the importance of understanding both genetic and environmental factors in nervous system disorders, including those with Mendelian inheritance patterns. A range of rodent models of other brain disorders, including Alzheimer's disease and Parkinson's disease, fragile X and Down syndrome, as well as various forms of brain injury, have now been compared under enriched and standard housing conditions. Here, we review these findings on the environmental modulators of pathogenesis and gene-environment interactions in CNS disorders, and discuss their therapeutic implications.
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Affiliation(s)
- Jess Nithianantharajah
- Howard Florey Institute, National Neuroscience Facility, University of Melbourne, Victoria 3010, Australia
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Wieloch T, Nikolich K. Mechanisms of neural plasticity following brain injury. Curr Opin Neurobiol 2006; 16:258-64. [PMID: 16713245 DOI: 10.1016/j.conb.2006.05.011] [Citation(s) in RCA: 235] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2006] [Accepted: 05/08/2006] [Indexed: 01/19/2023]
Abstract
Brain insults cause rapid cell death, and a disruption of functional circuits, in the affected regions. As the injured tissue recovers from events associated with cell death, regenerative processes are activated that over months lead to a certain degree of functional recovery. Factors produced by new neurons and glia, axonal sprouting of surviving neurons, and new synapse formation help to re-establish some of the lost functions. The timing and location of such events is crucial in the success of the regenerative process. Comprehensive gene expression profiling and proteomic analyses have enabled a deeper molecular and cellular mechanistic understanding of post-injury brain regeneration. These new mechanistic insights are aiding the design of novel therapeutic modalities that enhance regeneration.
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Affiliation(s)
- Tadeusz Wieloch
- Laboratory for Experimental Brain Research, Wallenberg Neuroscience Center, University of Lund, BMCA13, 221 85 Lund, Sweden.
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Komitova M, Johansson BB, Eriksson PS. On neural plasticity, new neurons and the postischemic milieu: An integrated view on experimental rehabilitation. Exp Neurol 2006; 199:42-55. [PMID: 16631168 DOI: 10.1016/j.expneurol.2006.03.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Accepted: 03/05/2006] [Indexed: 12/18/2022]
Abstract
This review discusses actual and potential contributors to functional improvement after stroke injuries. Topics that will be covered are neuronal re-organization and sprouting, neural stem/progenitor cell activation and neuronal replacement, as well as the neuronal milieu defined by glia, inflammatory cells and blood vessel supply. It is well established that different types of neuronal plasticity ultimately lead to post-stroke recovery. However, an untapped potential which only recently has started to be extensively explored is neuronal replacement through endogenous or exogenous resources. Major experimental efforts are needed to achieve progress in this burgeoning area. The review stresses the importance of applying neurodevelopmental principles as well as performing a characterization of the role of the postischemic milieu when studying adult brain neural stem/progenitor cells. Integrated and multifaceted experimentation, incorporating actual and possible poststroke function modulators, will be necessary in order to determine future strategies that will ultimately enable considerable progress in the field of neurorehabilitation.
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Affiliation(s)
- Mila Komitova
- Arvid Carlsson Institute, Division for Clinical Neuroscience and Rehabilitation, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
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39
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Matsumori Y, Hong SM, Fan Y, Kayama T, Hsu CY, Weinstein PR, Liu J. Enriched environment and spatial learning enhance hippocampal neurogenesis and salvages ischemic penumbra after focal cerebral ischemia. Neurobiol Dis 2005; 22:187-98. [PMID: 16361108 DOI: 10.1016/j.nbd.2005.10.015] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2005] [Revised: 10/25/2005] [Accepted: 10/29/2005] [Indexed: 01/17/2023] Open
Abstract
Enriched environment (EE) has been shown to increase neurogenesis in the adult brain. The aim of this study is to determine the effect of EE and spatial learning on neurogenesis following ischemic stroke. Male adult SD rats were subjected to sham surgery or distal middle cerebral artery occlusion (MCAO). MCAO induced a transient increase followed by a sustained depression of progenitor cell proliferation and neuroblast production below baseline level in both ipsilateral and contralateral DG compared to sham. Increased neuronal differentiation and neurogenesis in the DG were observed in both sham and MCAO rats following 8 weeks in the EE combined with spatial learning, compared to rats housed in the standard environment. EE/Learning also restored the total number of neuroblasts in the DG after MCAO compared to sham. Furthermore, EE/learning enhanced the density of NeuN positive cells in the ischemic penumbra, though no new neurons were detected in this region.
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Affiliation(s)
- Yasuhiko Matsumori
- Department of Neurological Surgery (112C), University of California, San Francisco, CA 94121, USA
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40
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Nygren J, Wieloch T. Enriched environment enhances recovery of motor function after focal ischemia in mice, and downregulates the transcription factor NGFI-A. J Cereb Blood Flow Metab 2005; 25:1625-33. [PMID: 15917744 DOI: 10.1038/sj.jcbfm.9600157] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The purpose of this study was to investigate the effect of enriched environment on motor function after experimental stroke in mice, and to determine whether time in enriched environment affects functional recovery. Earlier investigations have shown that rats placed in an enriched environment after focal ischemia, remarkably improve motor function, but similar observations in mice have not been reported. In this study, we show that placing mice in an enriched environment for 3 h daily for 2 weeks, after transient (50 mins) occlusion of the middle cerebral artery, enhanced neurologic outcome. Continuous postischemic housing in the enriched environment likewise improved motor function, but mortality increased. Two weeks exposure to enriched environment followed by housing the mice in standard cages for 2 weeks, resulted in a loss of the improved motor function. In contrast, 4 weeks exposure to enriched environment led to an improved motor function and to a better maintenance of neurologic recovery. The expression levels of the immediate-early gene nerve growth factor-induced gene A at 2 to 3 weeks of recovery decreased in animals housed in enriched environment, implying this transcription factor in the recovery process. We conclude that housing mice in an enriched environment after experimental stroke improves functional outcome. Also, the presented experimental procedure is useful for further studies of the genomics of functional recovery after experimental stroke.
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Affiliation(s)
- Josefine Nygren
- Laboratory for Experimental Brain Research, Wallenberg Neuroscience Center, Lund University, Lund, Sweden.
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41
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Rönnbäck A, Dahlqvist P, Svensson PA, Jernås M, Carlsson B, Carlsson LMS, Olsson T. Gene expression profiling of the rat hippocampus one month after focal cerebral ischemia followed by enriched environment. Neurosci Lett 2005; 385:173-8. [PMID: 15964140 DOI: 10.1016/j.neulet.2005.05.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2005] [Revised: 05/07/2005] [Accepted: 05/09/2005] [Indexed: 10/25/2022]
Abstract
Functional recovery after experimental stroke in rats is enhanced by environmental enrichment by stimulating plastic changes in brain regions outside the lesion, but the molecular mechanisms are not known. We investigated the effect of environmental enrichment after focal cerebral ischemia on cognitive recovery and hippocampal gene expression using microarray analysis. Rats placed in enriched environment (EE) for 1 month after middle cerebral artery occlusion (MCAo) showed significantly improved spatial memory in the Morris water maze compared to rats housed alone after MCAo. Microarray analysis suggested several EE-induced differences in neuronal plasticity-related genes, but these changes could not be confirmed by quantitative real-time PCR. This study highlights some of the potential problems associated with gene expression profiling of brain tissues. Further studies at earlier time points and in additional subregions of the brain are of interest in the search for molecular mechanisms behind EE-induced neuronal plasticity after ischemic stroke.
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Affiliation(s)
- Annica Rönnbäck
- Department of Public Health and Clinical Medicine, Umeå University Hospital, S-901 85 Umeå, Sweden
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42
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Craft TKS, Glasper ER, McCullough L, Zhang N, Sugo N, Otsuka T, Hurn PD, DeVries AC. Social interaction improves experimental stroke outcome. Stroke 2005; 36:2006-11. [PMID: 16100018 DOI: 10.1161/01.str.0000177538.17687.54] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND PURPOSE Social interaction can have a profound effect on health. The purpose of the present study was to determine whether affiliative social interactions before and after stroke improve ischemic outcomes as assessed through histological analysis and behavioral assays. METHODS Male and female C57BL/6 mice were housed individually or with an ovariectomized female. Behavioral assessments were made 24 hours before 60 or 90 minutes of transient intraluminal middle cerebral artery occlusion (MCAO) or SHAM surgery and after 7 days of reperfusion. Two hours after behavioral testing on day 7, infarct size was determined by 2,3,5-triphenyltetrazolium histology, and blood samples were collected for assessment of corticosterone and C-reactive protein (CRP) concentrations. RESULTS Pair housing significantly decreased infarct size and improved contralateral paw use in 60-minute MCAO males and 90-minute MCAO females compared with socially isolated cohorts. Housing condition had no significant effect on infarct size in females that underwent 60 minutes of MCAO, but pair housing was associated with improved contralateral paw use relative to socially isolated mice. In a separate cohort of males, intraischemic CRP concentration was significantly reduced in pair-housed males relative to isolated males. CONCLUSIONS Affiliative interaction during the peri-ischemic period reduces intraischemic CRP concentration, decreases ischemic damage in male and female mice, and improves behavioral outcome.
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Affiliation(s)
- Tara K S Craft
- Department of Psychology, The Ohio State University, Columbus, OH 43210, USA
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43
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Rönnbäck A, Dahlqvist P, Bergström SA, Olsson T. Diurnal effects of enriched environment on immediate early gene expression in the rat brain. Brain Res 2005; 1046:137-44. [PMID: 15927552 DOI: 10.1016/j.brainres.2005.03.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2004] [Revised: 03/24/2005] [Accepted: 03/29/2005] [Indexed: 10/25/2022]
Abstract
Rodents housed in an enriched environment (EE) show increased neuronal plasticity with enhanced long-term potentiation and memory performance. We report an EE-induced increase in NGFI-A and Krox-20 mRNA expression exclusively during the dark period of the day. In addition, EE-housed rats showed considerable diurnal variation in NGFI-A, Krox-20, and NGFI-B mRNA expression which was absent in single-housed rats. Thus, EE-induced molecular changes are more evident during the dark phase when the rats have higher motor and exploratory activity. This is important to take into account in future studies of molecular mediators of experience-dependent neuronal plasticity.
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Affiliation(s)
- Annica Rönnbäck
- Department of Public Health and Clinical Medicine, Medicine, Umeå University Hospital, Sweden
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44
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Komitova M, Zhao LR, Gidö G, Johansson BB, Eriksson P. Postischemic exercise attenuates whereas enriched environment has certain enhancing effects on lesion-induced subventricular zone activation in the adult rat. Eur J Neurosci 2005; 21:2397-405. [PMID: 15932598 DOI: 10.1111/j.1460-9568.2005.04072.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Experimental stroke increases cell proliferation and neurogenesis in the subventricular zone (SVZ) and in the dentate gyrus subgranular zone (SGZ) in the adult mammalian brain. This study examined the effects of postischemic voluntary exercise (running wheel) and environmental enrichment on the SVZ and SGZ 1 week after focal cortical ischemia in adult spontaneously hypertensive rats. Immunohistochemical labeling was performed for incorporation of specific cell markers such as Ki67 and 5-bromodeoxyuridine (proliferating and newborn cells), terminal deoxynucleotidyl transferase-mediated dUTP in situ nick-end labeling (apoptotic cells), Sox-2 and glial fibrillary acidic protein (neural stem and progenitor cells), polysialylated neural cell adhesion molecule and doublecortin (neuroblasts). Postischemic exercise and environmental enrichment differentially modulated SVZ cell genesis but lacked effects on the SGZ. Lesion-induced proliferation of neural stem/progenitor cells and neuronal precursors was attenuated in stroke runners without any effects on apoptosis or neuronal migration in the forebrain. Running activity did not affect the SVZ in intact rats. In contrast to postischemic wheel running, postischemic environmental enrichment did not have attenuating effects on the ipsilateral SVZ and increased proliferating putative neural stem cells and neuronal precursors contralaterally. A significant functional improvement, assessed using a rotating pole, was observed only in the postischemically enriched group and was likely due to other types of plasticity than neuronal replacement at this early time point. It may be concluded that in contrast to enriched environment, exercise during the first postischemic week might be detrimental for regenerative processes initiated in the SVZ after stroke.
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Affiliation(s)
- Mila Komitova
- The Arvid Carlsson Institute at the Institute of Clinical Neuroscience, Medicinaregatan 11, Box 432, 405 30 Göteborg, Sweden.
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45
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Greenfield SA, Collins TFT. A neuroscientific approach to consciousness. PROGRESS IN BRAIN RESEARCH 2005; 150:11-23. [PMID: 16186012 DOI: 10.1016/s0079-6123(05)50002-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
For a neuroscientist, consciousness currently defies any formal operational definition. However, the phenomenon is distinct from self-consciousness: after all, one can "let oneself go," when experiencing extreme emotion, but still be accessing a sentiment, subjective, conscious state. This raw, basic subjective state does not appear to be an exclusive property of the human brain. There is no obvious qualitative transformation in either the anatomy or the physiology of the central nervous system of human or non-human animals, no phylogenetic Rubicon in the animal kingdom. Similarly, there is no clear ontogenetic line that is crossed as the brain grows in the womb, no single event or change in brain physiology, and certainly not at birth, when consciousness might be generated in an all-or-none fashion. A more plausible, and scientific, view of consciousness might be therefore that it is not a different property of the brain, some magic bullet, but that it is a consequence of a quantitative increase in the complexity of the human brain: consciousness will grow as brains grow. Hence, consciousness is most likely to be a continuously variable property of the brain, in both phylogenetic and ontogenetic terms. Here, we describe how modern techniques may be utilized to determine the physiological basis of consciousness.
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Affiliation(s)
- Susan A Greenfield
- Department of Pharmacology, Mansfield Road, University of Oxford, Oxford, OX1 3QT, UK.
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46
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Brown AW, Bjelke B, Fuxe K. Motor response to amphetamine treatment, task-specific training, and limited motor experience in a postacute animal stroke model. Exp Neurol 2004; 190:102-8. [PMID: 15473984 DOI: 10.1016/j.expneurol.2004.07.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Revised: 06/22/2004] [Accepted: 07/21/2004] [Indexed: 10/26/2022]
Abstract
Despite advances in acute treatment of ischemic cerebrovascular events, the most common clinical outcome is disabling neurological impairment. Despite experimental evidence that psychostimulant treatment can positively affect recovery rate after focal brain lesions, beyond rehabilitation therapies there are no currently accepted medical treatments indicated for diminishing neurological impairment after clinically established stroke. To test the effect of amphetamine, task-specific training, limiting motor experience, and their interaction on motor recovery in a postacute animal model of stroke, animals were nonaversively trained in beam walking before a unilateral photochemical sensorimotor cortex lesion and tested for 10 days after lesion. Animals were randomized to groups receiving: a single session of motor training 24 h after lesion; a single injection of amphetamine 2 mg/kg 24 h after lesion; beam-walking experience limited to testing on days 1 and 10 after lesion; and groups that received amphetamine treatment combined with training or combined with limited experience. Motor recovery was maximally enhanced by training, delayed by amphetamine treatment, and most negatively affected by limiting beam-walking experience during the recovery period. These findings support physical training after stroke, indicating that limiting physical activity negatively affects motor recovery and raises questions about the role of stimulant treatment to enhance motor recovery in the postacute phase after stroke.
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Affiliation(s)
- Allen W Brown
- Department of Physical Medicine and Rehabilitation, Mayo Clinic and Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
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47
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Will B, Galani R, Kelche C, Rosenzweig MR. Recovery from brain injury in animals: relative efficacy of environmental enrichment, physical exercise or formal training (1990-2002). Prog Neurobiol 2004; 72:167-82. [PMID: 15130708 DOI: 10.1016/j.pneurobio.2004.03.001] [Citation(s) in RCA: 261] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2003] [Accepted: 02/25/2004] [Indexed: 11/19/2022]
Abstract
In the 1960s, it was shown for the first time that enriched housing enhances functional recovery after brain damage. During the 1970s and 1980s, many findings similar to this initial one have been reported, enlarging greatly its generality. Over the last 13 years, many different kinds of brain damage were modelled in animals or even directly studied in humans. Overall, these recent studies corroborated earlier findings, although occasional exceptions were reported. Other critical data, obtained mainly in intact animals, showed that enriched housing increases neurogenesis in the adult hippocampus. Recent evidence that this neurogenesis is involved in hippocampal-dependent learning supports the original interpretation of the enrichment effects as being the result of an accumulation of informal learning experiences (e.g., [. Heredity, environment, brain biochemistry, and learning. In: Current Trends in Psychological Theory. University of Pittsburgh Press, Pittsburgh, pp. 87-110;. Brain changes in response to experience. Sci. Am. 226, 22-29]). Other components of enriched environment, such as physical exercise, may have additive effects with those of training. The comparison of the relative effectiveness of enriched experience, of physical exercise and of training on structural and/or functional assessments of recovery, shows that training/learning is generally more effective than physical exercise and that enriched experience is a more potent therapy than either of these two other treatments. The combination of enriched experience with some other neurosurgical and/or neuropharmacological treatments may further improve its therapeutic effectiveness. Finally, other recent reports emphasize that the treatment parameters may be changed in order to approximate clinical/rehabilitation conditions and, nevertheless, remain effective.
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Affiliation(s)
- Bruno Will
- Laboratoire de Neurosciences Comportementales et Cognitives, Institut Fédératif des Neurosciences, Université Louis Pasteur, UMR 7521, CNRS, Strasbourg, France.
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48
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Dahlqvist P, Rönnbäck A, Bergström SA, Söderström I, Olsson T. Environmental enrichment reverses learning impairment in the Morris water maze after focal cerebral ischemia in rats. Eur J Neurosci 2004; 19:2288-98. [PMID: 15090055 DOI: 10.1111/j.0953-816x.2004.03248.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cognitive impairment is common after ischemic stroke. In rodent stroke models using occlusion of the middle cerebral artery (MCA) this is reflected by impaired spatial memory associated with the size of the ischemic lesion. Housing in an enriched environment enhances brain plasticity and improves recovery of sensorimotor functions after experimental stroke in rats. In this study we report that postischemic housing in an enriched environment also attenuates the long-term spatial memory impairment after MCA occlusion and extinguishes the association between spatial memory and infarct volume. An enriched environment did not significantly alter the expression of selected neuronal plasticity-associated genes 1 month after MCA occlusion, indicating that most of the adaptive changes induced by an enriched environment have already occurred at this time point. We conclude that the attenuated memory impairment induced by environmental enrichment after MCA occlusion provides a useful model for further studies on the neurobiological mechanisms of recovery of cognitive functions after ischemic stroke.
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Affiliation(s)
- Per Dahlqvist
- Department of Public Health and Clinical Medicine, Umeå University Hospital, S-901 85 Umeå, Sweden
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Mlynarik M, Johansson BB, Jezova D. Enriched Environment Influences Adrenocortical Response to Immune Challenge and Glutamate Receptor Gene Expression in Rat Hippocampus. Ann N Y Acad Sci 2004; 1018:273-80. [PMID: 15240378 DOI: 10.1196/annals.1296.032] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Housing of animals in an enriched environment (EE) has many positive effects on brain structure and function and can facilitate recovery from various brain injuries. The purpose of this study was to evaluate whether enriched rearing could alter the stress response induced by repeated immune challenge and to investigate the influence of EE and immune challenge on glutamate receptor gene expression in the hippocampus. Male 2-mo-old Wistar rats were kept under standard conditions (SC) or in an EE for 5 weeks. Immune challenge was performed by Escherichia coli lipopolysaccharide (LPS) injected repeatedly (ip) in increasing doses (10, 20, and 40 microg/kg/mL) once daily for five consecutive days. The animals were decapitated 2 h after the last injection. Blood samples, adrenals, and hippocampi were collected. LPS induced an increase in plasma and adrenal levels of corticosterone and a transient decrease in body weight of animals kept under SC, but not in an EE. Enriched housing resulted in an increase in adrenal weights and enhanced gene expression of hippocampal AMPA GluR1 receptor subunit. Concerning the LPS treatment, no effects on adrenal and thymus weights and glutamate receptor mRNA levels in the hippocampus were noticed. Thus, vulnerability to some negative effects of repeated immune challenge may be modified by environmental conditions associated with changes in brain plasticity. The fact that differences in housing conditions change stress response has to be considered in biomedical research.
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Affiliation(s)
- Martin Mlynarik
- Laboratory of Pharmacological Neuroendocrinology, Institute of Experimental Endocrinology, Slovak Academy of Sciences, Vlarska 3, Bratislava 833 06, Slovakia.
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Keyvani K, Sachser N, Witte OW, Paulus W. Gene Expression Profiling in the Intact and Injured Brain Following Environmental Enrichment. J Neuropathol Exp Neurol 2004; 63:598-609. [PMID: 15217088 DOI: 10.1093/jnen/63.6.598] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An enriched environment promotes structural changes in both injured and intact brain and improves behavioral performance. In 2 different experimental approaches, the effects of enriched surroundings were analyzed utilizing DNA microarrays. First, gene expression patterns of the sensorimotor cortex and the hippocampus of noninjured adult rats with enriched housing were compared with analogous regions of rats kept in standard cages. Second, circumscribed infarcts affecting the forelimb area of the sensorimotor cortex were induced, and gene expression patterns of the non-necrotic ipsilesional as well as the contralesional homotopic cortex of rats (postlesionally enriched housing versus standard) were analyzed. In the intact brain, the hippocampus, which had 43 upregulations and 15 downregulations showed more changes than the sensorimotor cortex, which had 13 upregulations and 4 downregulations, indicating a greater responsiveness of the hippocampus to environmental stimuli. In the injured brain, enrichment led ipsilesionally to 28 downregulations and 14 upregulations, while in the contralesional cortex, upregulations prevailed with 46 upregulations and 13 downregulations. The larger number of genes responsive to enrichment in the contralesional cortex (59 gene regulations) as compared to the analogous area (i.e. sensorimotor cortex) of the intact brain (17 gene regulations) likely reflects increased susceptibility for plastic changes due to injury. With the exception of the perilesional cortex, similar functional groups of genes were differentially regulated in different brain regions/paradigms, suggesting basically similar molecular cascades being involved in reorganizing the brain following external stimuli. Many of the genes detected here correspond to molecular pathways known to be involved in neuroplasticity, whereas others provide new and hitherto unrecognized entry points.
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Affiliation(s)
- Kathy Keyvani
- Institute of Neuropathology, University Hospital, Muenster, Germany.
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