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Stuckey SM, Ong LK, Collins-Praino LE, Turner RJ. Neuroinflammation as a Key Driver of Secondary Neurodegeneration Following Stroke? Int J Mol Sci 2021; 22:ijms222313101. [PMID: 34884906 PMCID: PMC8658328 DOI: 10.3390/ijms222313101] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/25/2021] [Accepted: 12/01/2021] [Indexed: 01/13/2023] Open
Abstract
Ischaemic stroke involves the rapid onset of focal neurological dysfunction, most commonly due to an arterial blockage in a specific region of the brain. Stroke is a leading cause of death and common cause of disability, with over 17 million people worldwide suffering from a stroke each year. It is now well-documented that neuroinflammation and immune mediators play a key role in acute and long-term neuronal tissue damage and healing, not only in the infarct core but also in distal regions. Importantly, in these distal regions, termed sites of secondary neurodegeneration (SND), spikes in neuroinflammation may be seen sometime after the initial stroke onset, but prior to the presence of the neuronal tissue damage within these regions. However, it is key to acknowledge that, despite the mounting information describing neuroinflammation following ischaemic stroke, the exact mechanisms whereby inflammatory cells and their mediators drive stroke-induced neuroinflammation are still not fully understood. As a result, current anti-inflammatory treatments have failed to show efficacy in clinical trials. In this review we discuss the complexities of post-stroke neuroinflammation, specifically how it affects neuronal tissue and post-stroke outcome acutely, chronically, and in sites of SND. We then discuss current and previously assessed anti-inflammatory therapies, with a particular focus on how failed anti-inflammatories may be repurposed to target SND-associated neuroinflammation.
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Affiliation(s)
- Shannon M. Stuckey
- Discipline of Anatomy and Pathology, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5005, Australia; (S.M.S.); (L.E.C.-P.)
| | - Lin Kooi Ong
- School of Pharmacy, Monash University Malaysia, Subang Jaya 47500, Malaysia;
- School of Biomedical Sciences and Pharmacy and the Priority Research Centre for Stroke and Brain Injury, The University of Newcastle, Callaghan 2308, Australia
| | - Lyndsey E. Collins-Praino
- Discipline of Anatomy and Pathology, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5005, Australia; (S.M.S.); (L.E.C.-P.)
| | - Renée J. Turner
- Discipline of Anatomy and Pathology, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5005, Australia; (S.M.S.); (L.E.C.-P.)
- Correspondence: ; Tel.: +61-8-8313-3114
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Zhang D, Lu Y, Zhao X, Zhang Q, Li L. Aerobic exercise attenuates neurodegeneration and promotes functional recovery - Why it matters for neurorehabilitation & neural repair. Neurochem Int 2020; 141:104862. [PMID: 33031857 DOI: 10.1016/j.neuint.2020.104862] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 12/19/2022]
Abstract
Aerobic exercise facilitates optimal neurological function and exerts beneficial effects in neurologic injuries. Both animal and clinical studies have shown that aerobic exercise reduces brain lesion volume and improves multiple aspects of cognition and motor function after stroke. Studies using animal models have proposed a wide range of potential molecular mechanisms that underlie the neurological benefits of aerobic exercise. Furthermore, additional exercise parameters, including time of initiation, exercise dosage (exercise duration and intensity), and treatment modality are also critical for clinical application, as identifying the optimal combination of parameters will afford patients with maximal functional gains. To clarify these issues, the current review summarizes the known neurological benefits of aerobic exercise under both physiological and pathological conditions and then considers the molecular mechanisms underlying these benefits in the contexts of stroke-like focal cerebral ischemia and cardiac arrest-induced global cerebral ischemia. In addition, we explore the key roles of exercise parameters on the extent of aerobic exercise-induced neurological benefits to elucidate the optimal combination for aerobic exercise intervention. Finally, the current challenges for aerobic exercise implementation after stroke are discussed.
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Affiliation(s)
- Dandan Zhang
- Department of General Practice & Geriatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Yujiao Lu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Xudong Zhao
- Department of General Practice & Geriatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China
| | - Quanguang Zhang
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
| | - Lei Li
- Department of General Practice & Geriatrics, Affiliated Hospital of Xuzhou Medical University, Xuzhou, Jiangsu, 221002, China.
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Abbasian S, Rastegar MM M. Is the Intensity or Duration of Treadmill Training Important for Stroke Patients? A Meta-Analysis. J Stroke Cerebrovasc Dis 2018; 27:32-43. [DOI: 10.1016/j.jstrokecerebrovasdis.2017.09.061] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 08/20/2017] [Accepted: 09/29/2017] [Indexed: 11/26/2022] Open
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Aidar FJ, de Oliveira RJ, de Matos DG, Mazini Filho ML, Moreira OC, de Oliveira CEP, Hickner RC, Reis VM. A Randomized Trial Investigating the Influence of Strength Training on Quality of Life in Ischemic Stroke. Top Stroke Rehabil 2016; 23:84-9. [DOI: 10.1080/10749357.2015.1110307] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Nishioka R, Sugimoto K, Aono H, Mise A, Choudhury ME, Miyanishi K, Islam A, Fujita T, Takeda H, Takahashi H, Yano H, Tanaka J. Treadmill exercise ameliorates ischemia-induced brain edema while suppressing Na⁺/H⁺ exchanger 1 expression. Exp Neurol 2015; 277:150-161. [PMID: 26724742 DOI: 10.1016/j.expneurol.2015.12.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/15/2015] [Accepted: 12/22/2015] [Indexed: 01/23/2023]
Abstract
Exercise may be one of the most effective and sound therapies for stroke; however, the mechanisms underlying the curative effects remain unclear. In this study, the effects of forced treadmill exercise with electric shock on ischemic brain edema were investigated. Wistar rats were subjected to transient (90 min) middle cerebral artery occlusion (tMCAO). Eighty nine rats with substantially large ischemic lesions were evaluated using magnetic resonance imaging (MRI) and were randomly assigned to exercise and non-exercise groups. The rats were forced to run at 4-6m/s for 10 min/day on days 2, 3 and 4. Brain edema was measured on day 5 by MRI, histochemical staining of brain sections and tissue water content determination (n=7, each experiment). Motor function in some rats was examined on day 30 (n=6). Exercise reduced brain edema (P<0.05-0.001, varied by the methods) and ameliorated motor function (P<0.05). The anti-glucocorticoid mifepristone or the anti-mineralocorticoid spironolactone abolished these effects, but orally administered corticosterone mimicked the ameliorating effects of exercise. Exercise prevented the ischemia-induced expression of mRNA encoding aquaporin 4 (AQP4) and Na(+)/H(+) exchangers (NHEs) (n=5 or 7, P<0.01). Microglia and NG2 glia expressed NHE1 in the peri-ischemic region of rat brains and also in mixed glial cultures. Corticosterone at ~10nM reduced NHE1 and AQP4 expression in mixed glial and pure microglial cultures. Dexamethasone and aldosterone at 10nM did not significantly alter NHE1 and AQP4 expression. Exposure to a NHE inhibitor caused shrinkage of microglial cells. These results suggest that the stressful short-period and slow-paced treadmill exercise suppressed NHE1 and AQP4 expression resulting in the amelioration of brain edema at least partly via the moderate increase in plasma corticosterone levels.
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Affiliation(s)
- Ryutaro Nishioka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Kana Sugimoto
- Department of Legal Medicine, Graduate School of Medicine/Faculty of Medicine, Osaka University, Japan
| | - Hitomi Aono
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Ayano Mise
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Mohammed E Choudhury
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Kazuya Miyanishi
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Afsana Islam
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Takahiro Fujita
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Haruna Takeda
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Hisaaki Takahashi
- Center for Advanced Research and Education, Asahikawa Medical University, Japan
| | - Hajime Yano
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Graduate School of Medicine, Ehime University, Japan.
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Physical Exercise as a Diagnostic, Rehabilitation, and Preventive Tool: Influence on Neuroplasticity and Motor Recovery after Stroke. Neural Plast 2015; 2015:608581. [PMID: 26682073 PMCID: PMC4670869 DOI: 10.1155/2015/608581] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 06/03/2015] [Accepted: 06/18/2015] [Indexed: 01/19/2023] Open
Abstract
Stroke remains a leading cause of adult motor disabilities in the world and accounts for the greatest number of hospitalizations for neurological disease. Stroke treatments/therapies need to promote neuroplasticity to improve motor function. Physical exercise is considered as a major candidate for ultimately promoting neural plasticity and could be used for different purposes in human and animal experiments. First, acute exercise could be used as a diagnostic tool to understand new neural mechanisms underlying stroke physiopathology. Indeed, better knowledge of stroke mechanisms that affect movements is crucial for enhancing treatment/rehabilitation effectiveness. Secondly, it is well established that physical exercise training is advised as an effective rehabilitation tool. Indeed, it reduces inflammatory processes and apoptotic marker expression, promotes brain angiogenesis and expression of some growth factors, and improves the activation of affected muscles during exercise. Nevertheless, exercise training might also aggravate sensorimotor deficits and brain injury depending on the chosen exercise parameters. For the last few years, physical training has been combined with pharmacological treatments to accentuate and/or accelerate beneficial neural and motor effects. Finally, physical exercise might also be considered as a major nonpharmacological preventive strategy that provides neuroprotective effects reducing adverse effects of brain ischemia. Therefore, prestroke regular physical activity may also decrease the motor outcome severity of stroke.
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Neuroprotection of Early Locomotor Exercise Poststroke: Evidence From Animal Studies. Can J Neurol Sci 2015; 42:213-20. [PMID: 26041314 DOI: 10.1017/cjn.2015.39] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Early locomotor exercise after stroke has attracted a great deal of attention in clinical and animal research in recent years. A series of animal studies showed that early locomotor exercise poststroke could protect against ischemic brain injury and improve functional outcomes through the promotion of angiogenesis, inhibition of acute inflammatory response and neuron apoptosis, and protection of the blood-brain barrier. However, to date, the clinical application of early locomotor exercise poststroke was limited because some clinicians have little confidence in its effectiveness. Here we review the current progress of early locomotor exercise poststroke in animal models. We hope that a comprehensive awareness of the early locomotor exercise poststroke may help to implement early locomotor exercise more appropriately in treatment for ischemic stroke.
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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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Wong R, Bath PMW, Kendall D, Gibson CL. Progesterone and cerebral ischaemia: the relevance of ageing. J Neuroendocrinol 2013; 25:1088-94. [PMID: 23631651 DOI: 10.1111/jne.12042] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/18/2013] [Accepted: 04/26/2013] [Indexed: 12/15/2022]
Abstract
Cerebral stroke is a leading cause of long-term disability and a major cause of death in the developed world. The total incidence of stroke is projected to rise substantially over the next 20 years as a result of the rising elderly population. Although age is one of the most significant prognostic markers for poor outcome after stroke, very few experimental studies have been conducted in aged animals. Importantly, sex differences in both vulnerability to stroke and outcome after cerebral ischaemia have frequently been reported and attributed to the action of steroid hormones. Progesterone is a candidate neuroprotective factor for stroke, although the majority of pre-clinical studies have focused on using young, healthy adult animals. In terms of cerebral stroke, males and postmenopausal females represent the groups at highest risk of cerebral stroke and these categories can be modelled using either aged or ovariectomised female animals. In this review, we discuss the importance of conducting experimental studies in aged animals compared to young, healthy animals, as well as the impact this has on experimental outcomes. In addition, we focus on reviewing the studies that have been conducted to date examining the neuroprotective potential of progesterone in aged animals. Importantly, the limited studies that have been conducted in aged animals do lend further support to progesterone as a therapeutic option after ischaemic stroke that warrants further investigation.
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Affiliation(s)
- R Wong
- Division of Stroke, University of Nottingham, Nottingham, UK
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Seubert J, Freiherr J, Djordjevic J, Lundström JN. Statistical localization of human olfactory cortex. Neuroimage 2012; 66:333-42. [PMID: 23103688 DOI: 10.1016/j.neuroimage.2012.10.030] [Citation(s) in RCA: 133] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022] Open
Abstract
Functional neuroimaging methods have been used extensively during the last decades to explore the neural substrates of olfactory processing. While a general consensus on the functional anatomy of olfactory cortex is beginning to emerge, the mechanisms behind the functions of individual processing nodes still remain debated. Further, it remains unclear to which extent divergent findings result from differences in methodological approaches. Using Activation Likelihood Estimation (ALE), the aim of the present study was to statistically combine all published data on functional neuroimaging of olfaction to provide a probability map reflecting the state of the field to date. Additionally, we grouped studies according to various methodological approaches to investigate whether these systematically affected the reported findings. A total of 45 studies (69 contrasts, 594 foci) met our inclusion criteria. Significant ALE peaks for odor against baseline were observed in areas commonly labeled as primary and secondary olfactory cortex, such as the piriform and orbitofrontal cortex, amygdala, anterior insula, and ventral putamen. In addition, differences were observed in the extent to which different methods were able to induce activation in these different nodes of the olfactory network.
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Affiliation(s)
| | - Jessica Freiherr
- Clinic for Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | | | - Johan N Lundström
- Monell Chemical Senses Center, Philadelphia, PA, USA; Department of Psychology, University of Pennsylvania, PA, USA; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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Liu F, McCullough LD. Interactions between age, sex, and hormones in experimental ischemic stroke. Neurochem Int 2012; 61:1255-65. [PMID: 23068990 DOI: 10.1016/j.neuint.2012.10.003] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 10/01/2012] [Accepted: 10/05/2012] [Indexed: 12/27/2022]
Abstract
Age, sex, and gonadal hormones have profound effects on ischemic stroke outcomes, although how these factors impact basic stroke pathophysiology remains unclear. There is a plethora of inconsistent data reported throughout the literature, primarily due to differences in the species examined, the timing and methods used to evaluate injury, the models used, and confusion regarding differences in stroke incidence as seen in clinical populations vs. effects on acute neuroprotection or neurorepair in experimental stroke models. Sex and gonadal hormone exposure have considerable independent impact on stroke outcome, but these factors also interact with each other, and the contribution of each differs throughout the lifespan. The contribution of sex and hormones to experimental stroke will be the focus of this review. Recent advances and our current understanding of age, sex, and hormone interactions in ischemic stroke with a focus on inflammation will be discussed.
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Affiliation(s)
- Fudong Liu
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT, USA
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Yang YR, Chang HC, Wang PS, Wang RY. Motor Performance Improved by Exercises in Cerebral Ischemic Rats. J Mot Behav 2012; 44:97-103. [DOI: 10.1080/00222895.2012.654524] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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The influence of the level of physical activity and human development in the quality of life in survivors of stroke. Health Qual Life Outcomes 2011; 9:89. [PMID: 21992748 PMCID: PMC3203027 DOI: 10.1186/1477-7525-9-89] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2011] [Accepted: 10/13/2011] [Indexed: 02/05/2023] Open
Abstract
Background The association between physical activity and quality of life in stroke survivors has not been analyzed within a framework related to the human development index. This study aimed to identify differences in physical activity level and in the quality of life of stroke survivors in two cities differing in economic aspects of the human development index. Methods Two groups of subjects who had suffered a stroke at least a year prior to testing and showed hemiplegia or hemiparesis were studied: a group from Belo Horizonte (BH) with 48 people (51.5 ± 8.7 years) and one from Montes Claros (MC) with 29 subjects (55.4 ± 8.1 years). Subsequently, regardless of location, the groups were divided into Active and Insufficiently Active so their difference in terms of quality of life could be analyzed. Results There were no significant differences between BH and MCG when it came to four dimensions of physical health that were evaluated (physical functioning, physical aspect, pain and health status) or in the following four dimensions of mental health status (vitality, social aspect, emotional aspect and mental health). However, significantly higher mean values were found in Active when compared with Insufficiently Active individuals in various measures of physical health (physical functioning 56.2 ± 4.4 vs. 47.4 ± 6.9; physical aspect 66.5 ± 6.5 vs. 59.1 ± 6.7; pain 55.9 ± 6.2 vs. 47.7 ± 6.0; health status 67.2 ± 4.2 vs. 56.6 ± 7.8) (arbitrary units), and mental health (vitality 60.9 ± 6.8 vs. 54.1 ± 7.2; social aspect 60.4 ± 7.1 vs. 54.2 ± 7.4; emotional aspect 64.0 ± 5.5 vs. 58.1 ± 6.9; mental health status 66.2 ± 5.5 vs. 58.4 ± 7.5) (arbitrary units). Conclusions Despite the difference between the cities concerning HDI values, no significant differences in quality of life were found between BH and MCG. However, the Active group showed significantly better results, confirming the importance of active lifestyle to enhance quality of life in stroke survivors.
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Liu N, Huang H, Lin F, Chen A, Zhang Y, Chen R, Du H. Effects of treadmill exercise on the expression of netrin-1 and its receptors in rat brain after cerebral ischemia. Neuroscience 2011; 194:349-58. [PMID: 21820492 DOI: 10.1016/j.neuroscience.2011.07.037] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2011] [Revised: 07/13/2011] [Accepted: 07/14/2011] [Indexed: 11/26/2022]
Abstract
Recent evidence suggests that exercise improves functional outcome in animal models of cerebral ischemia. Since netrin-1 and its receptors, deleted in colorectal cancer (DCC) and uncoordinated gene 5B (Unc5B), act as important regulators in neural and vascular activities, we sought to determine whether netrin-1 and DCC and Unc5B are involved in the neuroprotective effects of exercise on rats with induced cerebral ischemia. A total of 108 rats were randomly distributed into three groups: sham-operated group (n = 12), middle cerebral artery occlusion (MCAO) group (n = 48), MCAO+treadmill exercise group (n = 48). Behavioral testing indicated that treadmill exercise could significantly improve neurologic deficits of rats with cerebral ischemia at day 14 and 28 after MCAO (n = 12, P<0.05 and P<0.01), but there was no significant difference at day 4 and 7. Quantitative reverse transcription polymerase chain reaction (qPCR) and Western blot analysis revealed that treadmill exercise enhanced netrin-1 and DCC expression, while it suppressed Unc5B expression in rat peri-ischemic brain area, especially at day 14 and 28 after MCAO (n = 4, P<0.05 or P<0.01). Immunofluorescence analysis showed that in the peri-ischemic area, netrin-1 was expressed in neuronal perikarya, DCC, however, was expressed in neural processes and peri-vascular astrocytes, while Unc5B was expressed mostly in neuronal perikarya and some processes. These results suggest that netrin-1 and its receptors DCC and Unc5B may engage in exercise-induced neural circuit remodeling in the peri-ischemic area, and exercise may promote survival of neurons in this area by regulating netrin-1-Unc5B signaling. Additionally, netrin-1 may also play a role in brain-blood barrier via DCC-immunoreactive peri-vascular astrocytes. In conclusion, we demonstrate that treadmill exercise has beneficial effects that may be attributed, at least in part, to the involvement of netrin-1 and its receptors DCC and Unc5B in the neuronal and vascular activities in brain-ischemic rats.
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Affiliation(s)
- N Liu
- Department of Rehabilitation, The Affiliated Union Hospital of Fujian Medical University, 29 Xinquan Road, Fuzhou, Fujian 350001, PR China.
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Kim SJ, Kim BK, Ko YJ, Bang MS, Kim MH, Han TR. Functional and histologic changes after repeated transcranial direct current stimulation in rat stroke model. J Korean Med Sci 2010; 25:1499-505. [PMID: 20890433 PMCID: PMC2946662 DOI: 10.3346/jkms.2010.25.10.1499] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2010] [Accepted: 08/06/2010] [Indexed: 11/20/2022] Open
Abstract
Transcranial direct current stimulation (tDCS) is associated with enhancement or weakening of the NMDA receptor activity and change of the cortical blood flow. Therefore, repeated tDCS of the brain with cerebrovascular injury will induce the functional and histologic changes. Sixty-one Sprague-Dawley rats with cerebrovascular injury were used. Twenty rats died during the experimental course. The 41 rats that survived were allocated to the exercise group, the anodal stimulation group, the cathodal stimulation group, or the control group according to the initial motor function. Two-week treatment schedules started from 2 days postoperatively. Garcia, modified foot fault, and rota-rod performance scores were checked at 2, 9, and 16 days postoperatively. After the experiments, rats were sacrificed for the evaluation of histologic changes (changes of the white matter axon and infarct volume). The anodal stimulation and exercise groups showed improvement of Garcia's and modified foot fault scores at 16 days postoperatively. No significant change of the infarct volume happened after exercise and tDCS. Neuronal axons at the internal capsule of infarct hemispheres showed better preserved axons in the anodal stimulation group. From these results, repeated tDCS might have a neuroprotective effect on neuronal axons in rat stroke model.
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Affiliation(s)
- Sang Jun Kim
- Department of Rehabilitation Medicine, Seoul National University, College of Medicine, Seoul, Korea
| | - Byeong Kwon Kim
- Department of Pathology, Seoul National University, College of Medicine, Seoul, Korea
| | - Young Jin Ko
- Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, Seoul, Korea
| | - Moon Suk Bang
- Department of Rehabilitation Medicine, Seoul National University, College of Medicine, Seoul, Korea
| | - Man Ho Kim
- Department of Neurology, Seoul National University, College of Medicine, Seoul, Korea
| | - Tai Ryoon Han
- Department of Rehabilitation Medicine, Seoul National University, College of Medicine, Seoul, Korea
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