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Hunt RD, Cipolla MJ. Chronic hypertension alters the relationship between collateral blood flow, cortical cerebral blood flow, and brain tissue oxygenation. J Cereb Blood Flow Metab 2024:271678X241258569. [PMID: 38806143 DOI: 10.1177/0271678x241258569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
This study measured the relationship between pial collateral (leptomeningeal anastomoses, LMA) flow, intraparenchymal cortical cerebral blood flow (cCBF) and brain tissue oxygenation (btO2) during acute ischemic stroke to investigate how pial flow translates to downstream cCBF and btO2 and examined how this relationship is altered in hypertension. Proximal transient middle cerebral artery occlusion (tMCAO) was performed in male Wistar (n = 8/group) and Spontaneously Hypertensive Rats (SHR, n = 8/group). A combination laser Doppler-oxygen probe was placed within the expected cortical peri-infarct in addition to a surface laser doppler probe which measured LMA flow. Phenylephrine (PE) was infused 30 minutes into tMCAO to increase blood pressure (BP) by 30% for 10 minutes and assessed CBF autoregulation. During the initial 30-minute period of tMCAO, btO2 and cCBF were lower in SHR compared to Wistar rats (btO2: 11.5 ± 10.5 vs 17.5 ± 10.8 mmHg and cCBF: -29.7 ± 23.3% vs -17.8 ± 41.9%); however, LMA flow was similar between groups. The relationship between LMA flow, cCBF and btO2 were interdependent in Wistar rats. However, this relationship was disrupted in SHR rats and partially restored by induced hypertension. This study provides evidence that cCBF and btO2 were diminished during tMCAO in chronic hypertension, and that induced hypertension was beneficial regardless of hypertensive status.
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Affiliation(s)
- Ryan D Hunt
- Department of Neurological Sciences, University of Vermont, Larner College of Medicine, Burlington, VT, USA
| | - Marilyn J Cipolla
- Department of Neurological Sciences, University of Vermont, Larner College of Medicine, Burlington, VT, USA
- Department of Electrical and Biomedical Engineering, University of Vermont, College of Engineering and Mathematical Sciences, Burlington, VT, USA
- Department of Pharmacology, University of Vermont, Larner College of Medicine, Burlington, VT, USA
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Vermont, Larner College of Medicine, Burlington, VT, USA
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Franx B, Dijkhuizen RM, Dippel DWJ. Acute Ischemic Stroke in the Clinic and the Laboratory: Targets for Translational Research. Neuroscience 2024:S0306-4522(24)00159-3. [PMID: 38670254 DOI: 10.1016/j.neuroscience.2024.04.006] [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: 01/03/2024] [Revised: 03/26/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024]
Abstract
Ischemic stroke research has enabled significant advancements in diagnosis, treatment, and management of this debilitating disease, yet challenges remain standing in the way of better patient prognoses. In this narrative review, a fictional case illustrates challenges and uncertainties that medical professionals still face - penumbra identification, lack of neuroprotective agents, side-effects of tissue plasminogen activator, dearth of molecular biomarkers, incomplete microvascular reperfusion or no-reflow, post-recanalization hyperperfusion, blood pressure management and procedural anesthetic effects. The current state of the field is broadly reviewed per topic, with the aim to introduce a broad audience (scientist and clinician alike) to recent successes in translational stroke research and pending scientific queries that are tractable for preclinical assessment. Opportunities for co-operation between clinical and experimental stroke experts are highlighted to increase the size and frequency of strides the field makes to improve our understanding of this disease and ways of treating it.
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Affiliation(s)
- Bart Franx
- Translational Neuroimaging Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, the Netherlands
| | - Rick M Dijkhuizen
- Translational Neuroimaging Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, the Netherlands
| | - Diederik W J Dippel
- Stroke Center, Dept of Neurology, Erasmus University Medical Center, Rotterdam, the Netherlands.
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van der Knaap N, Franx BAA, Majoie CBLM, van der Lugt A, Dijkhuizen RM. Implications of Post-recanalization Perfusion Deficit After Acute Ischemic Stroke: a Scoping Review of Clinical and Preclinical Imaging Studies. Transl Stroke Res 2024; 15:179-194. [PMID: 36653525 PMCID: PMC10796479 DOI: 10.1007/s12975-022-01120-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 01/20/2023]
Abstract
The goal of reperfusion therapy for acute ischemic stroke (AIS) is to restore cerebral blood flow through recanalization of the occluded vessel. Unfortunately, successful recanalization does not always result in favorable clinical outcome. Post-recanalization perfusion deficits (PRPDs), constituted by cerebral hypo- or hyperperfusion, may contribute to lagging patient recovery rates, but its clinical significance remains unclear. This scoping review provides an overview of clinical and preclinical findings on post-ischemic reperfusion, aiming to elucidate the pattern and consequences of PRPD from a translational perspective. The MEDLINE database was searched for quantitative clinical and preclinical studies of AIS reporting PRPD based on cerebral circulation parameters acquired by translational tomographic imaging methods. PRPD and stroke outcome were mapped on a charting table, creating an overview of PRPD after AIS. Twenty-two clinical and twenty-two preclinical studies were included. Post-recanalization hypoperfusion is rarely reported in clinical studies (4/22) but unequivocally associated with detrimental outcome. Post-recanalization hyperperfusion is more commonly reported (18/22 clinical studies) and may be associated with positive or negative outcome. PRPD has been replicated in animal studies, offering mechanistic insights into causes and consequences of PRPD and allowing delineation of possible courses of PRPD. Complex relationships exist between PRPD and stroke outcome. Diversity in methods and lack of standardized definitions in reperfusion studies complicate the characterization of reperfusion patterns. Recommendations are made to advance the understanding of PRPD mechanisms and to further disentangle the relation between PRPD and disease outcome.
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Affiliation(s)
- Noa van der Knaap
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands
| | - Bart A A Franx
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands.
| | - Charles B L M Majoie
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Center, Location University of Amsterdam, Amsterdam, The Netherlands
| | - Aad van der Lugt
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht and Utrecht University, Utrecht, The Netherlands.
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Cipolla MJ. Therapeutic Induction of Collateral Flow. Transl Stroke Res 2023; 14:53-65. [PMID: 35416577 PMCID: PMC10155807 DOI: 10.1007/s12975-022-01019-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/31/2022] [Accepted: 04/01/2022] [Indexed: 01/31/2023]
Abstract
Therapeutic induction of collateral flow as a means to salvage tissue and improve outcome from acute ischemic stroke is a promising approach in the era in which endovascular therapy is no longer time-dependent but collateral-dependent. The importance of collateral flow enhancement as a therapeutic for acute ischemic stroke extends beyond those patients with large amounts of salvageable tissue. It also has the potential to extend the time window for reperfusion therapies in patients who are ineligible for endovascular thrombectomy. In addition, collateral enhancement may be an important adjuvant to neuroprotective agents by providing a more robust vascular route for which treatments can gain access to at risk tissue. However, our understanding of collateral hemodynamics, including under comorbid conditions that are highly prevalent in the stroke population, has hindered the efficacy of collateral flow augmentation for improving stroke outcome in the clinical setting. This review will discuss our current understanding of pial collateral function and hemodynamics, including vasoactivity that is critical for enhancing penumbral perfusion. In addition, mechanisms by which collateral flow can be increased during acute ischemic stroke to limit ischemic injury, that may be different depending on the state of the brain and vasculature prior to stroke, will also be reviewed.
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Affiliation(s)
- Marilyn J Cipolla
- Department of Neurological Sciences, University of Vermont Robert Larner College of Medicine, 149 Beaumont Ave, HSRF 416A, Burlington, VT, USA.
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Vermont Larner College of Medicine, Burlington, VT, USA.
- Department of Pharmacology, University of Vermont Larner College of Medicine, Burlington, VT, USA.
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Cipolla MJ, Chan SL. Impact of Acute and Chronic Hypertension on Changes in Pial Collateral Tone In Vivo During Transient Ischemia. Hypertension 2020; 76:1019-1026. [PMID: 32683904 DOI: 10.1161/hypertensionaha.120.15356] [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] [Indexed: 02/06/2023]
Abstract
We investigated vasoconstrictive responses of pial collaterals in vivo at baseline and during transient middle cerebral artery occlusion during chronic hypertension. A cranial window was used to measure diameter of leptomeningeal anastomoses (pial collaterals) in male Wistar (n=8) and spontaneously hypertensive rats (SHRs; n=8) using video dimensional analysis. Middle cerebral artery occlusion was induced by remote filament for 2 hours with 2 hours reperfusion. Phenylephrine was infused during ischemia as a pressor therapy. Active diameters of pial collaterals were significantly smaller in SHRs versus Wistar (14.1±1.5 versus 21.6±2.8 µm; P<0.01); however, passive diameters were similar (25.0±2.9 versus 25.0±2.6 µm; P>0.05). Basal tone of pial collaterals before occlusion was 42±5% in SHRs versus 15±4% in Wistar (P<0.01). Tone decreased in both Wistar and SHRs during occlusion but remained higher in SHRs (9±2% versus 29±4%; P<0.05). Phenylephrine increased blood pressure in both groups but had little effect on leptomeningeal anastomoses diameters. Reperfusion caused vasoconstriction of pial collaterals, increasing tone from 8±1% to 20±5% in Wistar and 29±5% to 44±5% in SHRs (P<0.01). Higher tone in pial collaterals from SHRs basally and during occlusion/reperfusion could limit flow to the penumbra and promote evolution of infarction. Sustained elevated tone of pial collaterals from SHRs with phenylephrine suggests pressor therapy may not be appropriate during chronic hypertension.
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Affiliation(s)
- Marilyn J Cipolla
- From the Departments of Neurological Sciences, Obstetrics, Gynecology and Reproductive Sciences, and Pharmacology, University of Vermont Larner College of Medicine, Burlington
| | - Siu-Lung Chan
- From the Departments of Neurological Sciences, Obstetrics, Gynecology and Reproductive Sciences, and Pharmacology, University of Vermont Larner College of Medicine, Burlington
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Gutiérrez-Vargas JA, Cardona-Gómez GP. Considering risk factors for the effectiveness of translational therapies in brain stroke. J Neurol Sci 2020; 408:116547. [PMID: 31683050 DOI: 10.1016/j.jns.2019.116547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 09/10/2019] [Accepted: 10/18/2019] [Indexed: 11/17/2022]
Abstract
Multiple studies on cerebral ischemia have been performed in animal models to propose different strategies of neuroprotection that mitigate either the early or late consequences of the disease. These therapies have been successful in reducing the volume of infarction, the proinflammatory cascade, and the amount of free radicals, as well as reversing markers of neurodegeneration, among other events. However, when those strategies are translated to clinical studies, their effectiveness is not reproduced. This review will focus on highlighting some of the main limitations of the animal models of stroke that lead to unsuccessful translational therapies and the common risk factors in humans that should be carefully considered in the experimental design of future studies to generate a more realistic spatiotemporal physiopathology and improve therapeutic efficacy in cerebral ischemia.
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Affiliation(s)
| | - Gloria Patricia Cardona-Gómez
- Grupo de Neurociencias de Antioquia, Área de Neurobiología Celular y Molecular, Facultad de Medicina, SIU, Universidad de Antioquia, Calle 70 No. 52-21, Medellín, Colombia
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Cipolla MJ, Liebeskind DS, Chan SL. The importance of comorbidities in ischemic stroke: Impact of hypertension on the cerebral circulation. J Cereb Blood Flow Metab 2018; 38:2129-2149. [PMID: 30198826 PMCID: PMC6282213 DOI: 10.1177/0271678x18800589] [Citation(s) in RCA: 180] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Comorbidities are a hallmark of stroke that both increase the incidence of stroke and worsen outcome. Hypertension is prevalent in the stroke population and the most important modifiable risk factor for stroke. Hypertensive disorders promote stroke through increased shear stress, endothelial dysfunction, and large artery stiffness that transmits pulsatile flow to the cerebral microcirculation. Hypertension also promotes cerebral small vessel disease through several mechanisms, including hypoperfusion, diminished autoregulatory capacity and localized increase in blood-brain barrier permeability. Preeclampsia, a hypertensive disorder of pregnancy, also increases the risk of stroke 4-5-fold compared to normal pregnancy that predisposes women to early-onset cognitive impairment. In this review, we highlight how comorbidities and concomitant disorders are not only risk factors for ischemic stroke, but alter the response to acute ischemia. We focus on hypertension as a comorbidity and its effects on the cerebral circulation that alters the pathophysiology of ischemic stroke and should be considered in guiding future therapeutic strategies.
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Affiliation(s)
- Marilyn J Cipolla
- 1 Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT, USA
| | - David S Liebeskind
- 2 Neurovascular Imaging Research Core and Stroke Center, Department of Neurology, University of California at Los Angeles, Los Angeles, CA, USA
| | - Siu-Lung Chan
- 1 Department of Neurological Sciences, University of Vermont Larner College of Medicine, Burlington, VT, USA
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Naessens DMP, de Vos J, VanBavel E, Bakker ENTP. Blood-brain and blood-cerebrospinal fluid barrier permeability in spontaneously hypertensive rats. Fluids Barriers CNS 2018; 15:26. [PMID: 30244677 PMCID: PMC6151927 DOI: 10.1186/s12987-018-0112-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 08/23/2018] [Indexed: 12/04/2022] Open
Abstract
Background Hypertension is an important risk factor for cerebrovascular disease, including stroke and dementia. Both in humans and animal models of hypertension, neuropathological features such as brain atrophy and oedema have been reported. We hypothesised that cerebrovascular damage resulting from chronic hypertension would manifest itself in a more permeable blood–brain barrier and blood–cerebrospinal fluid barrier. In addition, more leaky barriers could potentially contribute to an enhanced interstitial fluid and cerebrospinal fluid formation, which could, in turn, lead to an elevated intracranial pressure. Methods To study this, we monitored intracranial pressure and estimated the cerebrospinal fluid production rate in spontaneously hypertensive (SHR) and normotensive rats (Wistar Kyoto, WKY) at 10 months of age. Blood–brain barrier and blood–cerebrospinal fluid barrier integrity was determined by measuring the leakage of fluorescein from the circulation into the brain and cerebrospinal fluid compartment. Prior to sacrifice, a fluorescently labelled lectin was injected into the bloodstream to visualise the vasculature and subsequently study a number of specific vascular characteristics in six different brain regions. Results Blood and brain fluorescein levels were not different between the two strains. However, cerebrospinal fluid fluorescein levels were significantly lower in SHR. This could not be explained by a difference in cerebrospinal fluid turnover, as cerebrospinal fluid production rates were similar in SHR and WKY, but may relate to a larger ventricular volume in the hypertensive strain. Also, intracranial pressure was not different between SHR and WKY. Morphometric analysis of capillary volume fraction, number of branches, capillary diameter, and total length did not reveal differences between SHR and WKY. Conclusion In conclusion, we found no evidence for blood–brain barrier or blood–cerebrospinal fluid barrier leakage to a small solute, fluorescein, in rats with established hypertension. Electronic supplementary material The online version of this article (10.1186/s12987-018-0112-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daphne M P Naessens
- Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Judith de Vos
- Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Ed VanBavel
- Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Erik N T P Bakker
- Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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Gubskiy IL, Namestnikova DD, Cherkashova EA, Chekhonin VP, Baklaushev VP, Gubsky LV, Yarygin KN. MRI Guiding of the Middle Cerebral Artery Occlusion in Rats Aimed to Improve Stroke Modeling. Transl Stroke Res 2018; 9:417-425. [PMID: 29178027 PMCID: PMC6061245 DOI: 10.1007/s12975-017-0590-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/11/2017] [Accepted: 11/17/2017] [Indexed: 01/30/2023]
Abstract
The middle cerebral artery occlusion (MCAO) model in rats closely imitates ischemic stroke and is widely used. Existing instrumental methods provide a certain level of MCAO guidance, but monitoring of the MCA-occluding intraluminal filament position and possible complications can be improved. The goal of this study was to develop a MRI-based method of simultaneous control of the filament position, blood flow in the intracranial vessels, and hemorrhagic complications. Rats were subjected to either MRI-guided MCAO (group 1, n = 51) or MCAO without MRI control (group 2, n = 38). After operation, group 1 rats were transferred into a MRI scanner for the control of the filament position and possible complications. Ninety minutes after the onset of MCAO, the filament was removed in rats of both groups and MRI control of the infarct volume and hemorrhagic complications performed. High-resolution T1- and T2-weighted imaging performed immediately after filament insertion provided visualization of the filament position, blood flow in brain arteries, and complications related to inappropriate filament insertion. It permitted replacement of wrongly positioned filaments and exclusion of animals with complications from the experiment. MRI-based MCAO guiding provided real-time intra-operational monitoring of crucial parameters determining MCAO suitability for stroke modeling, including better assessment of the operation outcomes in individual animals and significant enhancement of the model success rate. The possibility of simultaneous visualization of the filament, blood flow in the arteries, brain tissue, and hemorrhagic complications is the principal advantage of the proposed method over other instrumental methods of MCAO quality control. Graphical Abstract MRI-guided middle cerebral artery occlusion technique permits intra-operational monitoring via direct non-invasive simultaneous visualization of the filament, blood flow in the arteries, brain tissue, and hemorrhagic complications. It provides better assessment of MCAO outcomes in individual animals and significant enhancement of MCAO success rate.
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Affiliation(s)
- Ilya L Gubskiy
- Research Institute of Cerebrovascular Pathology and Stroke, Pirogov Russian National Research Medical University, Moscow, Russia.
| | - Daria D Namestnikova
- Department of Neurology, Neurosurgery and Medical Genetics, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Elvira A Cherkashova
- Department of Neurology, Neurosurgery and Medical Genetics, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Vladimir P Chekhonin
- Serbsky Federal Medical Research Centre of Psychiatry and Narcology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Vladimir P Baklaushev
- Federal Research Clinical Center of Specialized Medical Care and Medical Technologies of the FMBA of Russia, Moscow, Russia
| | - Leonid V Gubsky
- Research Institute of Cerebrovascular Pathology and Stroke, Pirogov Russian National Research Medical University, Moscow, Russia
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Choi SH, Arai AL, Mou Y, Kang B, Yen CCC, Hallenbeck J, Silva AC. Neuroprotective Effects of MAGL (Monoacylglycerol Lipase) Inhibitors in Experimental Ischemic Stroke. Stroke 2018; 49:718-726. [PMID: 29440474 DOI: 10.1161/strokeaha.117.019664] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 01/03/2018] [Accepted: 01/11/2018] [Indexed: 12/24/2022]
Abstract
BACKGROUND AND PURPOSE MAGL (monoacylglycerol lipase) is an enzyme that hydrolyzes the endocannabinoid 2-arachidonoylglycerol and regulates the production of arachidonic acid and prostaglandins-substances that mediate tissue inflammatory response. Here, we have studied the effects of the selective MAGL inhibitors JZL184 and MJN110 and their underlying molecular mechanisms on 3 different experimental models of focal cerebral ischemia. METHODS SHR (spontaneously hypertensive rats) and normotensive WKY (Wistar Kyoto) rats were subject to an intracortical injection of the potent vasoconstrictor endothelin-1, permanent occlusion of a distal segment of the middle cerebral artery via craniectomy, or transient occlusion of the middle cerebral artery by the intraluminal suture method. JZL184 or MJN110 was administered 60 minutes after focal cerebral ischemia. Infarct volumes, hemispheric swelling, and functional outcomes were assessed between days 1 to 28 by magnetic resonance imaging, histology, and behavioral tests. RESULTS Pharmacological inhibition of MAGL significantly attenuated infarct volume and hemispheric swelling. MAGL inhibition also ameliorated sensorimotor deficits, suppressed inflammatory response, and decreased the number of degenerating neurons. These beneficial effects of MAGL inhibition were not fully abrogated by selective antagonists of cannabinoid receptors, indicating that the anti-inflammatory effects are caused by inhibition of eicosanoid production rather than by activation of cannabinoid receptors. CONCLUSIONS Our results suggest that MAGL may contribute to the pathophysiology of focal cerebral ischemia and is thus a promising therapeutic target for the treatment of ischemic stroke.
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Affiliation(s)
- Sang-Ho Choi
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - Allison L Arai
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - Yongshan Mou
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - Byeongteck Kang
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - Cecil Chern-Chyi Yen
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - John Hallenbeck
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.)
| | - Afonso C Silva
- From the Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging (S.-H.C., A.A., C.C.-C.Y., A.C.S.); National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (Y.M., J.H.); and College of Veterinary Medicine, Chungbuk National University, Cheongju, Korea (B.K.).
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Cerebrovascular Gene Expression in Spontaneously Hypertensive Rats After Transient Middle Cerebral Artery Occlusion. Neuroscience 2017; 367:219-232. [PMID: 29102661 DOI: 10.1016/j.neuroscience.2017.10.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 10/22/2017] [Accepted: 10/24/2017] [Indexed: 12/12/2022]
Abstract
Hypertension is a major risk factor for stroke, which is one of the leading global causes of death. In the search for new and effective therapeutic targets in stroke research, we need to understand the influence of hypertension in the vasculature following stroke. We used Affymetrix whole-transcriptome expression profiling as a tool to address gene expression differences between the occluded and non-occluded middle cerebral arteries (MCAs) from spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats after transient middle cerebral artery occlusion (tMCAO), to provide clues about the pathological mechanisms set in play after stroke. Verified by quantitative PCR, expression of Ccl2, Edn1, Tgfβ2, Olr1 and Serpine1 was significantly increased in the occluded compared to non-occluded MCAs from both SHRs and WKY rats. Additionally, expression of Mmp9, Icam1, Hif1α and Timp1 was increased in the occluded compared to non-occluded MCAs isolated from WKY rats. In comparison between occluded MCAs from SHRs versus occluded MCAs from WKY rats, expression of Ccl2, Olr1 and Serpine1 was significantly increased in SHR MCAs. However, the opposite was observed regarding expression of Edn1. Thus these data suggest that Ccl2, Edn1, Tgfβ2, Olr1 and Serpine1 may be possible mediators of the vascular changes in the occluded MCAs from both SHRs and WKY rats after tMCAO. The aforementioned genes possess biological functions that are consistent with early stroke injuries. In conclusion, these genes may be potential targets in future strategies for acute stroke treatments that can be used in patients with and without hypertension.
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12
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Effects of hyperoxia on 18F-fluoro-misonidazole brain uptake and tissue oxygen tension following middle cerebral artery occlusion in rodents: Pilot studies. PLoS One 2017; 12:e0187087. [PMID: 29091934 PMCID: PMC5665507 DOI: 10.1371/journal.pone.0187087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Accepted: 10/15/2017] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Mapping brain hypoxia is a major goal for stroke diagnosis, pathophysiology and treatment monitoring. 18F-fluoro-misonidazole (FMISO) positron emission tomography (PET) is the gold standard hypoxia imaging method. Normobaric hyperoxia (NBO) is a promising therapy in acute stroke. In this pilot study, we tested the straightforward hypothesis that NBO would markedly reduce FMISO uptake in ischemic brain in Wistar and spontaneously hypertensive rats (SHRs), two rat strains with distinct vulnerability to brain ischemia, mimicking clinical heterogeneity. METHODS Thirteen adult male rats were randomized to distal middle cerebral artery occlusion under either 30% O2 or 100% O2. FMISO was administered intravenously and PET data acquired dynamically for 3hrs, after which magnetic resonance imaging (MRI) and tetrazolium chloride (TTC) staining were carried out to map the ischemic lesion. Both FMISO tissue uptake at 2-3hrs and FMISO kinetic rate constants, determined based on previously published kinetic modelling, were obtained for the hypoxic area. In a separate group (n = 9), tissue oxygen partial pressure (PtO2) was measured in the ischemic tissue during both control and NBO conditions. RESULTS As expected, the FMISO PET, MRI and TTC lesion volumes were much larger in SHRs than Wistar rats in both the control and NBO conditions. NBO did not appear to substantially reduce FMISO lesion size, nor affect the FMISO kinetic rate constants in either strain. Likewise, MRI and TTC lesion volumes were unaffected. The parallel study showed the expected increases in ischemic cortex PtO2 under NBO, although these were small in some SHRs with very low baseline PtO2. CONCLUSIONS Despite small samples, the apparent lack of marked effects of NBO on FMISO uptake suggests that in permanent ischemia the cellular mechanisms underlying FMISO trapping in hypoxic cells may be disjointed from PtO2. Better understanding of FMISO trapping processes will be important for future applications of FMISO imaging.
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Abstract
Insulin resistance often refers to a pathological condition in which cells fail to respond to the normal actions of insulin. Increasing literature has noted a critical role of insulin resistance in the pathogenesis of ischemic stroke. Insulin resistance plays an important role in the pathogenesis of ischemic stroke via enhancing advanced changes of atherosclerosis. A variety of literature indicates that insulin resistance enhances platelet adhesion, activation and aggregation which are conducive to the occurrence of ischemic stroke. Insulin resistance also induces hemodynamic disturbances and contributes to the onset of ischemic stroke. In addition, insulin resistance may augment the role of the modifiable risk factors in ischemic stroke and induce the occurrence of ischemic stroke. Preclinical and clinical studies have supported that improving insulin resistance may be an effective measure to prevent or delay ischemic stroke.
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Affiliation(s)
- Xiao-Ling Deng
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan Renmin Hospital, Shiyan, 442000, Hubei Province, People's Republic of China
| | - Zhou Liu
- Department of Neurology, The Affiliated Hospital of Guangdong Medical University, and Institute of Neurology, Guangdong Medical University, Zhanjiang, Guangdong Province, People's Republic of China
| | - Chuanling Wang
- Department of Pathology, Chongqing Medical University, Chongqing, 400016, People's Republic of China
| | - Yanfeng Li
- Department of Neurology, Peking Union Medical College Hospital, No.1 Shuaifuyuan Wangfujing, Dongcheng District, Beijing, 100730, People's Republic of China.
| | - Zhiyou Cai
- Department of Neurology, Chongqing General Hospital, No. 312 Zhongshan First Road, Yuzhong District, Chongqing, 400013, People's Republic of China.
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Chan SL, Cipolla MJ. Treatment with low dose fasudil for acute ischemic stroke in chronic hypertension. J Cereb Blood Flow Metab 2017; 37:3262-3270. [PMID: 28665172 PMCID: PMC5584704 DOI: 10.1177/0271678x17718665] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We investigated the effect of Rho kinase inhibition on changes in cerebral blood flow (CBF), brain injury and vascular function after ischemic stroke in spontaneously hypertensive rats (SHR). Changes in core MCA and collateral perfusion were measured by a validated laser Doppler method. Animals underwent 2 h tMCAO and 2 h reperfusion. Fasudil (0.1 mg/kg, i.v.) or vehicle was given at 30 min ischemia (n = 9/group; mean (SD)). Brain injury was determined by 2,3,5-triphenyltetrazolium chloride staining. To determine the effect of fasudil on vascular function, fasudil was given 10 min before reperfusion and parenchymal arterioles studied isolated (n = 6/group; mean(SD)). Collateral perfusion was low in vehicle-treated SHR (-8(32)%) that changed minimally with fasudil (6(24)%, p > 0.05, effect size: 0.47;95% CI-0.49-1.39). Reperfusion CBF was below baseline in vehicle (-27(26)%) and fasudil (-32(25)%, p > 0.05, effect size: 0.19; 95% CI-0.74-1.11) groups, suggesting incomplete reperfusion in both groups. Fasudil had little effect on brain injury volume (28(13)% vs. 36(7)% in vehicle, p > 0.05, effect size: 0.75; 95% CI-0.24-1.66). In isolated parenchymal arterioles, myogenic tone was similar between groups (37(6)% vs. 38(10)% in vehicle, p > 0.05, effect size: 0.09; 95% CI-1.05-1.21). There were no differences with fasudil treatment vs. vehicle in perfusion, brain injury and vascular function that may be related to the low dose that had minimal blood pressure lowering effect.
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Affiliation(s)
- Siu-Lung Chan
- Departments of Neurological Sciences, Obstetrics, Gynecology & Reproductive Sciences, and Pharmacology, Larner, College of Medicine, University of Vermont, Burlington, VT, USA
| | - Marilyn J Cipolla
- Departments of Neurological Sciences, Obstetrics, Gynecology & Reproductive Sciences, and Pharmacology, Larner, College of Medicine, University of Vermont, Burlington, VT, USA
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15
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Liu S, Dai Q, Hua R, Liu T, Han S, Li S, Li J. Determination of Brain-Regional Blood Perfusion and Endogenous cPKCγ Impact on Ischemic Vulnerability of Mice with Global Ischemia. Neurochem Res 2017; 42:2814-2825. [DOI: 10.1007/s11064-017-2294-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/19/2017] [Accepted: 05/06/2017] [Indexed: 01/12/2023]
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Abstract
Inflammatory response plays an important role in the pathogenesis of ischemic stroke and anti-inflammatory agents may provide a choice of treatment. Triptolide is reported to be anti-inflammatory. In this study, we investigated the effects of triptolide on cultured neuronal cell line in vitro and experimental ischemic stroke in vivo. Oxygen-glucose deprivation (OGD) and tumor necrosis factor-α (TNF-α) stimulated SH-SY5Y cells were incubated with triptolide. In vivo, rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h, followed by reperfusion for 23 h. Results of this study showed that triptolide treatment reduced the OGD-induced cytotoxicity and apoptosis and blocked TNF-α-induced activation of NF-κB and p38MAPK in SH-SY5Y cells. Intraperitoneal injection of triptolide showed significant neuroprotective actions in stroke rats. Triptolide attenuated neurological deficit, brain infarct volume, and brain water content, and inhibited activation of NF-κB and p38MAPK. These data show that triptolide protects rats against ischemic cerebral injury via inhibiting NF-κB and p38MAPK signaling pathways.
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Affiliation(s)
- Maolin Hao
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong University, #4 Duanxing West Road, Jinan, 250022, Shandong, China,
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Chang CZ, Wu SC. 4'-O-β-D-Glucosyl-5-O-Methylvisamminol, A Natural Histone H3 Phosphorylation Epigenetic Suppressor, Exerts a Neuroprotective Effect Through PI3K/Akt Signaling Pathway on Focal Cerebral Ischemia in Rats. World Neurosurg 2016; 89:474-88. [PMID: 26868427 DOI: 10.1016/j.wneu.2016.01.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 01/15/2016] [Accepted: 01/19/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND A bursting inflammation has been observed that compromises neurologic function in patients who experience stroke. We sought to examine the neuroprotective efficacy of 4'-O-β-D-glucosyl-5-O-methylvisamminol (OGOMV), a novel histone H3 phosphorylation epigenetic suppressor) in a transient middle cerebral artery occlusion (tMCAO). METHODS A rodent tMCAO model was used. Administration with 400 μg/kg/day OGOMV was initiated 12 hours before (prevention) and 1 hour after animals were subjected to tMCAO (reversal). The cerebral cortex was harvested to examine protein kinase B (PI3D/Akt), 5-bromo-2'-deoxyuridine (Western blot), and caspases (reverse-transcription polymerase chain reaction). In addition, cerebrospinal fluid samples were collected to examine interleukin 1-β, interleukin-6, monocyte chemoattractant protein-1, and tumor necrosis factor-α (reverse-transcription polymerase chain reaction). RESULTS Cortical 5-bromo-2'-deoxyuridine and phospho-PI3D/Akt were reduced in tMCAO animals, compared with the healthy controls but increased in the OGOMV treatment and prevention groups. Activated cortical caspase-3,-6, and -9a as well as increased IL-1β and TNF-α levels were observed in the tMCAO animals (P < 0.05). Both prevention and treatment with OGOMV significantly reduced cleaved caspase-3 and -9a groups, but no significant change in caspase-6 was noted. Perifosine, an Akt inhibitor, was added to reduce the bioexpression of phospho-P13D/Akt, and Bcl-2 level and increased cleaved caspase-9a level in both OGOMV prevention and treatment tMCAO groups (P > 0.05). CONCLUSION Our study suggests that OGOMV could exert a neuroprotective effect by inhibiting the P13D/Akt protein, attenuating inflammation, and cleaved caspase-3- and -9a-related apoptosis. This study also lends credence to support the notion that the prevention of OGOMV could attenuate proinflammatory cytokine mRNA and late-onset caspases in tMCAO and merits further study.
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Affiliation(s)
- Chih-Zen Chang
- Department of Surgery, Faculty of Medicine, School of Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Surgery, Kaohsiung Municipal Ta Tung Hospital, Kaohsiung, Taiwan.
| | - Shu-Chuan Wu
- Division of Neurosurgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
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Möller K, Pösel C, Kranz A, Schulz I, Scheibe J, Didwischus N, Boltze J, Weise G, Wagner DC. Arterial Hypertension Aggravates Innate Immune Responses after Experimental Stroke. Front Cell Neurosci 2015; 9:461. [PMID: 26640428 PMCID: PMC4661280 DOI: 10.3389/fncel.2015.00461] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/12/2015] [Indexed: 01/13/2023] Open
Abstract
Arterial hypertension is not only the leading risk factor for stroke, but also attributes to impaired recovery and poor outcome. The latter could be explained by hypertensive vascular remodeling that aggravates perfusion deficits and blood–brain barrier disruption. However, besides vascular changes, one could hypothesize that activation of the immune system due to pre-existing hypertension may negatively influence post-stroke inflammation and thus stroke outcome. To test this hypothesis, male adult spontaneously hypertensive rats (SHRs) and normotensive Wistar Kyoto rats (WKYs) were subjected to photothrombotic stroke. One and 3 days after stroke, infarct volume and functional deficits were evaluated by magnetic resonance imaging and behavioral tests. Expression levels of adhesion molecules and chemokines along with the post-stroke inflammatory response were analyzed by flow cytometry, quantitative real-time PCR and immunohistochemistry in rat brains 4 days after stroke. Although comparable at day 1, lesion volumes were significantly larger in SHR at day 3. The infarct volume showed a strong correlation with the amount of CD45 highly positive leukocytes present in the ischemic hemispheres. Functional deficits were comparable between SHR and WKY. Brain endothelial expression of intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and P-selectin (CD62P) was neither increased by hypertension nor by stroke. However, in SHR, brain infiltrating myeloid leukocytes showed significantly higher surface expression of ICAM-1 which may augment leukocyte transmigration by leukocyte–leukocyte interactions. The expression of chemokines that primarily attract monocytes and granulocytes was significantly increased by stroke and, furthermore, by hypertension. Accordingly, ischemic hemispheres of SHR contain considerably higher numbers of monocytes, macrophages and granulocytes. Exacerbated brain inflammation in SHR may finally be responsible for larger infarct volumes. These findings provide an immunological explanation for the epidemiological observation that existing hypertension negatively affects stroke outcome and mortality.
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Affiliation(s)
- Karoline Möller
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Institute of Anatomy, Histology and Embryology, University of Leipzig Leipzig, Germany
| | - Claudia Pösel
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany
| | - Alexander Kranz
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany
| | - Isabell Schulz
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany
| | - Johanna Scheibe
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany
| | - Nadine Didwischus
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Research Group Human Biology, Institute of Biology, University of Leipzig Leipzig, Germany
| | - Johannes Boltze
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Fraunhofer Research Institution for Marine Biotechnology and Institute for Medical and Marine Biotechnology, University of Lübeck Lübeck, Germany
| | - Gesa Weise
- Fraunhofer Institute for Cell Therapy and Immunology Leipzig, Germany ; Department of Neurology, University of Leipzig Leipzig, Germany
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Yang T, Sun S, Wang T, Tong X, Bi J, Wang Y, Sun Z. Piperlonguminine is neuroprotective in experimental rat stroke. Int Immunopharmacol 2014; 23:447-51. [PMID: 25257731 DOI: 10.1016/j.intimp.2014.09.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 09/09/2014] [Accepted: 09/10/2014] [Indexed: 11/24/2022]
Abstract
Inflammatory damage plays an important role in cerebral ischemic pathogenesis and may represent a target for treatment. Piperlonguminine (PE) has been proved to have anti-inflammatory actions. In this study, we investigated the effects of PE on cultured neuronal cell line, SH-SY5Y in vitro and experimental rat ischemic stroke in vivo. For oxygen-glucose deprivation (OGD) and tumor necrosis factor-α (TNF-α) stimulated SH-SY5Y cell line in vitro, SH-SY5Y cells were incubated with PE. In vivo, rats were subjected to middle cerebral artery occlusion (MACO) for 1h, followed by reperfusion for 23 h. The results of this study showed that treatment of SH-SY5Y cells with PE reduced the OGD-induced cytotoxicity and apoptosis and blocked TNF-α-induced activation of NF-κB and MAPK. Intraperitoneal injection of PE (2.4 mg/kg) produced a significant neuroprotective potential in rats with cerebral ischemia. PE attenuated neurological deficit scores, brain infarct volume and brain water content in rats, and inhibited activation of NF-κB and MAPK. These data show that PE protects the brain against ischemic cerebral injury via alleviating blood-brain barrier (BBB) breakdown, which may be mediated via inhibiting NF-κB and MAPK signaling pathways.
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Affiliation(s)
- Tiansong Yang
- First Affiliated Hospital, Heilongjiang University of Chinese Medicine, PR China
| | - Shixiao Sun
- Department of Physiology, Heilongjiang University of Chinese Medicine, PR China
| | - Tiegang Wang
- The First Affiliated Hospital, Harbin Medical University, Harbin, PR China
| | - Xin Tong
- Atlantic Institute of Oriental Medicine (ATOM), FL, USA
| | - Junhui Bi
- Department of Formulas of Chinese Medicine, Heilongjiang University of Chinese Medicine, PR China
| | - Yulin Wang
- First Affiliated Hospital, Heilongjiang University of Chinese Medicine, PR China
| | - Zhongren Sun
- First Affiliated Hospital, Heilongjiang University of Chinese Medicine, PR China; Department of Acupuncture, Heilongjiang University of Chinese Medicine, PR China.
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