1
|
Foo LS, Larkin JR, Sutherland BA, Ray KJ, Yap WS, Goh CH, Hum YC, Lai KW, Harston G, Tee YK. Investigation of relayed nuclear Overhauser enhancement effect at -1.6 ppm in an ischemic stroke model. Quant Imaging Med Surg 2023; 13:7879-7892. [PMID: 38106293 PMCID: PMC10722023 DOI: 10.21037/qims-23-510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 08/28/2023] [Indexed: 12/19/2023]
Abstract
Background When an ischemic stroke happens, it triggers a complex signalling cascade that may eventually lead to neuronal cell death if no reperfusion. Recently, the relayed nuclear Overhauser enhancement effect at -1.6 ppm [NOE(-1.6 ppm)] has been postulated may allow for a more in-depth analysis of the ischemic injury. This study assessed the potential utility of NOE(-1.6 ppm) in an ischemic stroke model. Methods Diffusion-weighted imaging, perfusion-weighted imaging, and chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) data were acquired from five rats that underwent scans at 9.4 T after middle cerebral artery occlusion. Results The apparent diffusion coefficient (ADC), cerebral blood flow (CBF), and apparent exchange-dependent relaxations (AREX) at 3.5 ppm and NOE(-1.6 ppm) were quantified. AREX(3.5 ppm) and NOE(-1.6 ppm) were found to be hypointense and exhibited different signal patterns within the ischemic tissue. The NOE(-1.6 ppm) deficit areas were equal to or larger than the ADC deficit areas, but smaller than the AREX(3.5 ppm) deficit areas. This suggested that NOE(-1.6 ppm) might further delineate the acidotic tissue estimated using AREX(3.5 ppm). Since NOE(-1.6 ppm) is closely related to membrane phospholipids, NOE(-1.6 ppm) potentially highlighted at-risk tissue affected by lipid peroxidation and membrane damage. Altogether, the ADC/NOE(-1.6 ppm)/AREX(3.5 ppm)/CBF mismatches revealed four zones of increasing sizes within the ischemic tissue, potentially reflecting different pathophysiological information. Conclusions Using CEST coupled with ADC and CBF, the ischemic tissue may thus potentially be separated into four zones to better understand the pathophysiology after stroke and improve ischemic tissue fate definition. Further verification of the potential utility of NOE(-1.6 ppm) may therefore lead to a more precise diagnosis.
Collapse
Affiliation(s)
- Lee Sze Foo
- Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Malaysia
| | - James R. Larkin
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Brad A. Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Australia
| | - Kevin J. Ray
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Wun-She Yap
- Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Malaysia
| | - Choon-Hian Goh
- Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Malaysia
| | - Yan Chai Hum
- Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Malaysia
| | - Khin Wee Lai
- Faculty of Engineering, Department of Biomedical Engineering, University of Malaya, Kuala Lumpur, Malaysia
| | - George Harston
- Acute Stroke Service, Oxford University Hospitals National Health Service Foundation Trust, Oxford, UK
| | - Yee Kai Tee
- Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Malaysia
| |
Collapse
|
2
|
Msayib Y, Harston GWJ, Ray KJ, Larkin JR, Sutherland BA, Sheerin F, Blockley NP, Okell TW, Jezzard P, Baldwin A, Sibson NR, Kennedy J, Chappell MA. Quantitative chemical exchange saturation transfer imaging of nuclear overhauser effects in acute ischemic stroke. Magn Reson Med 2022; 88:341-356. [PMID: 35253936 PMCID: PMC9314583 DOI: 10.1002/mrm.29187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/07/2022]
Abstract
PURPOSE In chemical exchange saturation transfer imaging, saturation effects between - 2 to - 5 ppm (nuclear Overhauser effects, NOEs) have been shown to exhibit contrast in preclinical stroke models. Our previous work on NOEs in human stroke used an analysis model that combined NOEs and semisolid MT; however their combination might feasibly have reduced sensitivity to changes in NOEs. The aim of this study was to explore the information a 4-pool Bloch-McConnell model provides about the NOE contribution in ischemic stroke, contrasting that with an intentionally approximate 3-pool model. METHODS MRI data from 12 patients presenting with ischemic stroke were retrospectively analyzed, as well as from six animals induced with an ischemic lesion. Two Bloch-McConnell models (4 pools, and a 3-pool approximation) were compared for their ability to distinguish pathological tissue in acute stroke. The association of NOEs with pH was also explored, using pH phantoms that mimic the intracellular environment of naïve mouse brain. RESULTS The 4-pool measure of NOEs exhibited a different association with tissue outcome compared to 3-pool approximation in the ischemic core and in tissue that underwent delayed infarction. In the ischemic core, the 4-pool measure was elevated in patient white matter ( 1 . 20 ± 0 . 20 ) and in animals ( 1 . 27 ± 0 . 20 ). In the naïve brain pH phantoms, significant positive correlation between the NOE and pH was observed. CONCLUSION Associations of NOEs with tissue pathology were found using the 4-pool metric that were not observed using the 3-pool approximation. The 4-pool model more adequately captured in vivo changes in NOEs and revealed trends depending on tissue pathology in stroke.
Collapse
Affiliation(s)
- Yunus Msayib
- Institute of Biomedical Engineering, Department of Engineering ScienceUniversity of OxfordOxfordUK
| | - George W. J. Harston
- Acute Vascular Imaging Centre, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Kevin J. Ray
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - James R. Larkin
- Department of Oncology, CRUK and MRC Oxford Institute for Radiation OncologyUniversity of OxfordOxfordUK
| | - Brad A. Sutherland
- Acute Vascular Imaging Centre, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
- School of MedicineUniversity of TasmaniaHobartTasmaniaAustralia
| | - Fintan Sheerin
- Acute Vascular Imaging Centre, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Nicholas P. Blockley
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Thomas W. Okell
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | - Peter Jezzard
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
| | | | - Nicola R. Sibson
- Department of Oncology, CRUK and MRC Oxford Institute for Radiation OncologyUniversity of OxfordOxfordUK
| | - James Kennedy
- Acute Vascular Imaging Centre, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Michael A. Chappell
- Wellcome Centre for Integrative Neuroimaging, Nuffield Department of Clinical NeurosciencesUniversity of OxfordOxfordUK
- Sir Peter Mansfield Imaging Center, School of MedicineUniversity of NottinghamNottinghamUK
- Mental Health & Clinical Neuroscience, School of Medicine, University of NottinghamNottinghamUK
| |
Collapse
|
3
|
Fu Y, Xing R, Wang L, Yang L, Jiang B. Neurovascular protection of salvianolic acid B and ginsenoside Rg1 combination against acute ischemic stroke in rats. Neuroreport 2021; 32:1140-1146. [PMID: 34284451 DOI: 10.1097/wnr.0000000000001706] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ischemic stroke continues to be a major global health problem associated with considerable mortality and morbidity. Thus, it is still targeted by researchers for developing new strategies or drugs to alleviate the lesion of stroke. In the present study, both the permanent occlusion of the middle cerebral artery (MCAO) model and the restoration of cerebral blood flow after middle cerebral artery occlusion (CI/R) model were set up for evaluating the efficiency of salvianolic acid B and ginsenoside Rg1 combination (SalB-Rg1). SalB-Rg1 decreased infarct area through 3,5-triphenyltetrazolium chloride stain and improved neurological behavior through Longa Score or Left-Biased Swings on both MCAO rats and CI/R rats. Neural protection of SalB-Rg1 against ischemia or ischemic reperfusion injury was evidenced by the inhibition of nucleus pyknosis, liquefaction necrosis through H&E stain and Nissl stain. Furthermore, protection of SalB-Rg1 on blood-brain barrier (BBB) was more significant on CI/R rats, accompanying with the downregulation of matrix metalloproteinase-2 and matrix metalloproteinase-9, and recovery of zonula occludens-1 expression. These results provide compelling evidence that SalB-Rg1 holds the potential to be developed as an optimal therapeutic strategy to alleviate the injury of ischemia or ischemic reperfusion.
Collapse
Affiliation(s)
- Yao Fu
- State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Sciences, School of Chemical Engineering, Dalian University of Technology, Dalian
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Rongrong Xing
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Linlin Wang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Li Yang
- State Key Laboratory of Fine Chemicals, Department of Pharmaceutical Sciences, School of Chemical Engineering, Dalian University of Technology, Dalian
| | - Baohong Jiang
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| |
Collapse
|
4
|
Foo LS, Larkin JR, Sutherland BA, Ray KJ, Yap WS, Hum YC, Lai KW, Manan HA, Sibson NR, Tee YK. Study of common quantification methods of amide proton transfer magnetic resonance imaging for ischemic stroke detection. Magn Reson Med 2021; 85:2188-2200. [PMID: 33107119 DOI: 10.1002/mrm.28565] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/30/2020] [Accepted: 10/02/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE To assess the correlation and differences between common amide proton transfer (APT) quantification methods in the diagnosis of ischemic stroke. METHODS Five APT quantification methods, including asymmetry analysis and its variants as well as two Lorentzian model-based methods, were applied to data acquired from six rats that underwent middle cerebral artery occlusion scanned at 9.4T. Diffusion and perfusion-weighted images, and water relaxation time maps were also acquired to study the relationship of these conventional imaging modalities with the different APT quantification methods. RESULTS The APT ischemic area estimates had varying sizes (Jaccard index: 0.544 ≤ J ≤ 0.971) and had varying correlations in their distributions (Pearson correlation coefficient: 0.104 ≤ r ≤ 0.995), revealing discrepancies in the quantified ischemic areas. The Lorentzian methods produced the highest contrast-to-noise ratios (CNRs; 1.427 ≤ CNR ≤ 2.002), but generated APT ischemic areas that were comparable in size to the cerebral blood flow (CBF) deficit areas; asymmetry analysis and its variants produced APT ischemic areas that were smaller than the CBF deficit areas but larger than the apparent diffusion coefficient deficit areas, though having lower CNRs (0.561 ≤ CNR ≤ 1.083). CONCLUSION There is a need to further investigate the accuracy and correlation of each quantification method with the pathophysiology using a larger scale multi-imaging modality and multi-time-point clinical study. Future studies should include the magnetization transfer ratio asymmetry results alongside the findings of the study to facilitate the comparison of results between different centers and also the published literature.
Collapse
Affiliation(s)
- Lee Sze Foo
- Department of Mechatronics and Biomedical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Selangor, Malaysia
| | - James R Larkin
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
| | - Brad A Sutherland
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Kevin J Ray
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
| | - Wun-She Yap
- Department of Electrical and Electronic Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Selangor, Malaysia
| | - Yan Chai Hum
- Department of Mechatronics and Biomedical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Selangor, Malaysia
| | - Khin Wee Lai
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Jalan Universiti, Kuala Lumpur, Malaysia
| | - Hanani Abdul Manan
- Department of Radiology, Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia
| | - Nicola R Sibson
- Department of Oncology, Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
| | - Yee Kai Tee
- Department of Mechatronics and Biomedical Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Kajang, Selangor, Malaysia
| |
Collapse
|
5
|
Matrix Metalloproteinase-9 Expression is Enhanced by Ischemia and Tissue Plasminogen Activator and Induces Hemorrhage, Disability and Mortality in Experimental Stroke. Neuroscience 2021; 460:120-129. [PMID: 33465414 DOI: 10.1016/j.neuroscience.2021.01.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/29/2020] [Accepted: 01/04/2021] [Indexed: 12/29/2022]
Abstract
Matrix metalloproteinase-9 (MMP-9) degrades collagen and other cellular matrix proteins. After acute ischemic stroke, increased MMP-9 levels are correlated with hemorrhage, lack of reperfusion and stroke severity. Nevertheless, definitive data that MMP-9 itself causes poor outcomes in ischemic stroke are limited. In a model of experimental ischemic stroke with reperfusion, we examined whether ischemia and recombinant tissue plasminogen activator (r-tPA) therapy affected MMP-9 expression, and we used specific inhibitors to test if MMP-9 affects brain injury and recovery. After stroke, MMP-9 expression increased significantly in the ischemic vs. non-ischemic hemisphere of the brain (p < 0.001). MMP-9 expression in the ischemic, but not the non-ischemic hemisphere, was further increased by r-tPA treatment (p < 0.001). To determine whether MMP-9 expression contributed to stroke outcomes after r-tPA treatment, we tested three different antibody MMP-9 inhibitors. When compared to treatment with r-tPA and saline, treatment with r-tPA and MMP-9 antibody inhibitors significantly reduced brain hemorrhage by 11.3 to 38.6-fold (p < 0.01), brain swelling by 2.8 to 4.3-fold (p < 0.001) and brain infarction by 2.5 to 3.9-fold (p < 0.0001). Similarly, when compared to treatment with r-tPA and saline, treatment with r-tPA and an MMP-9 antibody inhibitor significantly improved neurobehavioral outcomes (p < 0.001), decreased weight loss (p < 0.001) and prolonged survival (p < 0.01). In summary, both prolonged ischemia and r-tPA selectively enhanced MMP-9 expression in the ischemic hemisphere. When administered with r-tPA, specific MMP-9 inhibitors markedly reduced brain hemorrhage, swelling, infarction, disability and death, which suggests that blocking the deleterious effects of MMP-9 may improve outcomes after ischemic stroke.
Collapse
|
6
|
Beard DJ, Li Z, Schneider AM, Couch Y, Cipolla MJ, Buchan AM. Rapamycin Induces an eNOS (Endothelial Nitric Oxide Synthase) Dependent Increase in Brain Collateral Perfusion in Wistar and Spontaneously Hypertensive Rats. Stroke 2020; 51:2834-2843. [PMID: 32772681 DOI: 10.1161/strokeaha.120.029781] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
BACKGROUND AND PURPOSE Rapamycin is a clinically approved mammalian target of rapamycin inhibitor that has been shown to be neuroprotective in animal models of stroke. However, the mechanism of rapamycin-induced neuroprotection is still being explored. Our aims were to determine if rapamycin improved leptomeningeal collateral perfusion, to determine if this is through eNOS (endothelial nitric oxide synthase)-mediated vessel dilation and to determine if rapamycin increases immediate postreperfusion blood flow. METHODS Wistar and spontaneously hypertensive rats (≈14 weeks old, n=22 and n=15, respectively) were subjected to ischemia by middle cerebral artery occlusion (90 and 120 minutes, respectively) with or without treatment with rapamycin at 30-minute poststroke. Changes in middle cerebral artery and collateral perfusion territories were measured by dual-site laser Doppler. Reactivity to rapamycin was studied using isolated and pressurized leptomeningeal anastomoses. Brain injury was measured histologically or with triphenyltetrazolium chloride staining. RESULTS In Wistar rats, rapamycin increased collateral perfusion (43±17%), increased reperfusion cerebral blood flow (16±8%) and significantly reduced infarct volume (35±6 versus 63±8 mm3, P<0.05). Rapamycin dilated leptomeningeal anastomoses by 80±9%, which was abolished by nitric oxide synthase inhibition. In spontaneously hypertensive rats, rapamycin increased collateral perfusion by 32±25%, reperfusion cerebral blood flow by 44±16%, without reducing acute infarct volume 2 hours postreperfusion. Reperfusion cerebral blood flow was a stronger predictor of brain damage than collateral perfusion in both Wistar and spontaneously hypertensive rats. CONCLUSIONS Rapamycin increased collateral perfusion and reperfusion cerebral blood flow in both Wistar and comorbid spontaneously hypertensive rats that appeared to be mediated by enhancing eNOS activation. These findings suggest that rapamycin may be an effective acute therapy for increasing collateral flow and as an adjunct therapy to thrombolysis or thrombectomy to improve reperfusion blood flow.
Collapse
Affiliation(s)
- Daniel J Beard
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, United Kingdom (D.J.B., A.M.S., Y.C., A.M.B.)
- School of Biomedical Science and Pharmacy, The University of Newcastle, Australia (D.J.B.)
| | - Zhaojin Li
- Department of Neurological Sciences, The University of Vermont, Burlington (Z.L., M.J.C.)
| | - Anna M Schneider
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, United Kingdom (D.J.B., A.M.S., Y.C., A.M.B.)
| | - Yvonne Couch
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, United Kingdom (D.J.B., A.M.S., Y.C., A.M.B.)
| | - Marilyn J Cipolla
- Department of Neurological Sciences, The University of Vermont, Burlington (Z.L., M.J.C.)
| | - Alastair M Buchan
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, United Kingdom (D.J.B., A.M.S., Y.C., A.M.B.)
| |
Collapse
|
7
|
Premilovac D, Blackwood SJ, Ramsay CJ, Keske MA, Howells DW, Sutherland BA. Transcranial contrast-enhanced ultrasound in the rat brain reveals substantial hyperperfusion acutely post-stroke. J Cereb Blood Flow Metab 2020; 40:939-953. [PMID: 32063081 PMCID: PMC7181087 DOI: 10.1177/0271678x20905493] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Direct and real-time assessment of cerebral hemodynamics is key to improving our understanding of cerebral blood flow regulation in health and disease states such as stroke. While a number of sophisticated imaging platforms enable assessment of cerebral perfusion, most are limited either spatially or temporally. Here, we applied transcranial contrast-enhanced ultrasound (CEU) to measure cerebral perfusion in real-time through the intact rat skull before, during and after ischemic stroke, induced by intraluminal filament middle cerebral artery occlusion (MCAO). We demonstrate expected decreases in cortical and striatal blood volume, flow velocity and perfusion during MCAO. After filament retraction, blood volume and perfusion increased two-fold above baseline, indicative of acute hyperperfusion. Adjacent brain regions to the ischemic area and the contralateral hemisphere had increased blood volume during MCAO. We assessed our data using wavelet analysis to demonstrate striking vasomotion changes in the ischemic and contralateral cortices during MCAO and reperfusion. In conclusion, we demonstrate the application of CEU for real-time assessment of cerebral hemodynamics and show that the ischemic regions exhibit striking hyperemia post-MCAO. Whether this post-stoke hyperperfusion is sustained long-term and contributes to stroke severity is not known.
Collapse
Affiliation(s)
- Dino Premilovac
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Sarah J Blackwood
- Åstrand Laboratory of Work Physiology, Swedish School of Sport and Health Sciences, GIH, Stockholm, Sweden
| | - Ciaran J Ramsay
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Michelle A Keske
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Victoria, Australia
| | - David W Howells
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Brad A Sutherland
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| |
Collapse
|
8
|
Hadley G, Beard DJ, Couch Y, Neuhaus AA, Adriaanse BA, DeLuca GC, Sutherland BA, Buchan AM. Rapamycin in ischemic stroke: Old drug, new tricks? J Cereb Blood Flow Metab 2019; 39:20-35. [PMID: 30334673 PMCID: PMC6311672 DOI: 10.1177/0271678x18807309] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/16/2018] [Accepted: 09/06/2018] [Indexed: 12/19/2022]
Abstract
The significant morbidity that accompanies stroke makes it one of the world's most devastating neurological disorders. Currently, proven effective therapies have been limited to thrombolysis and thrombectomy. The window for the administration of these therapies is narrow, hampered by the necessity of rapidly imaging patients. A therapy that could extend this window by protecting neurons may improve outcome. Endogenous neuroprotection has been shown to be, in part, due to changes in mTOR signalling pathways and the instigation of productive autophagy. Inducing this effect pharmacologically could improve clinical outcomes. One such therapy already in use in transplant medicine is the mTOR inhibitor rapamycin. Recent evidence suggests that rapamycin is neuroprotective, not only via neuronal autophagy but also through its broader effects on other cells of the neurovascular unit. This review highlights the potential use of rapamycin as a multimodal therapy, acting on the blood-brain barrier, cerebral blood flow and inflammation, as well as directly on neurons. There is significant potential in applying this old drug in new ways to improve functional outcomes for patients after stroke.
Collapse
Affiliation(s)
- Gina Hadley
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Daniel J Beard
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Yvonne Couch
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Ain A Neuhaus
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Bryan A Adriaanse
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Gabriele C DeLuca
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Brad A Sutherland
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- School of Medicine, College of Health and Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Alastair M Buchan
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Acute Vascular Imaging Centre, University of Oxford, Oxford University Hospitals, Oxford, UK
| |
Collapse
|
9
|
Ingberg E, Dock H, Theodorsson E, Theodorsson A, Ström JO. Effect of laser Doppler flowmetry and occlusion time on outcome variability and mortality in rat middle cerebral artery occlusion: inconclusive results. BMC Neurosci 2018; 19:24. [PMID: 29673328 PMCID: PMC5909274 DOI: 10.1186/s12868-018-0425-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 04/12/2018] [Indexed: 12/26/2022] Open
Abstract
Background Stroke is among the leading causes of death and disability. Although intense research efforts have provided promising treatment options in animals, most clinical trials in humans have failed and the therapeutic options are few. Several factors have been suggested to explain this translational difficulty, particularly concerning methodology and study design. Consistent infarcts and low mortality might be desirable in some, but not all, studies. Here, we aimed to investigate whether the use of laser Doppler flowmetry (LDF) and the occlusion time (60 vs. 45 min) affected outcome variability and mortality in a rat stroke model. Eighty ovariectomized female Wistar rats were subjected to ischemic stroke using intraluminal filament middle cerebral artery occlusion with or without LDF and with occlusion times of 45 or 60 min. Outcome was evaluated by triphenyl tetrazolium chloride staining of brain slices to measure infarct size and a modified sticky tape test. Results Neither LDF nor occlusion times of 45 versus 60 min significantly affected mortality, outcome variability or outcome severity. Conclusions Due to the unexpectedly high mortality and variability the statistical power was very low and thus the results were inconclusive. Electronic supplementary material The online version of this article (10.1186/s12868-018-0425-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Edvin Ingberg
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden. .,Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
| | - Hua Dock
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Elvar Theodorsson
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Annette Theodorsson
- Department of Neurosurgery and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Jakob O Ström
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Department of Neurology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| |
Collapse
|
10
|
Al-Sarraf H, Malatiali S, Al-Awadi M, Redzic Z. Effects of erythropoietin on astrocytes and brain endothelial cells in primary culture during anoxia depend on simultaneous signaling by other cytokines and on duration of anoxia. Neurochem Int 2017; 113:34-45. [PMID: 29180303 DOI: 10.1016/j.neuint.2017.11.014] [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: 09/11/2017] [Revised: 11/08/2017] [Accepted: 11/22/2017] [Indexed: 12/13/2022]
Abstract
Studies on animals revealed neuroprotective effects of exogenously applied erythropoietin (EPO) during cerebral ischemia/hypoxia. Yet, application of exogenous EPO in stroke patients often lead to haemorrhagic transformation. To clarify potential mechanism of this adverse effect we explored effects of EPO on viabilities of astrocytes and brain endothelial cells (BECs) in primary culture during anoxia of various durations, in the presence or absence of vascular endothelial growth factor (VEGF) and angiopoietin-1 (Ang1), which are cytokines that are also released from the neurovascular unit during hypoxia. Anoxia (2-48 h) exerted marginal effects on BECs' viability and significant reductions in viability of astrocytes. Astrocyte-conditioned medium did not exert effects and exerted detrimental effects on BECs during 2 h and 24 h anoxia, respectively. This was partially reversed by inhibition of Janus kinase (Jak)2/signal transducer and activator of transcription (STAT)5 activation. Addition of rat recombinant EPO (rrEPO) during 2 h-6h anoxia was protective for astrocytes, but had no effect on BECs. Addition of rrEPO significantly reduced viability of BECs and astrocytes after 48 h anoxia and after 24 h-48 h anoxia, respectively, which was attenuated by inhibition of Jak2/STAT5 activation. Simultaneous addition of rrEPO and VEGFA (1-165) caused marginal effects on BECs, but a highly significant protective effects on astrocytes during 24-48 h anoxia, which were attenuated by inhibition of Jak2/STAT5 activation. Simultaneous addition of EPO, VEGFA 1-165 and Ang1 exerted protective effects on BECs during 24 h-48 h anoxia, which were attenuated by addition of soluble Tie2 receptor. These data revealed that EPO could exert protective, but also injurious effects on BECs and astrocytes during anoxia, which depended on the duration of anoxia and on simultaneous signaling by VEGF and Ang1. If these injurious effects occur in stroke patients, they could enhance vascular damage and haemorrhagic transformation.
Collapse
Affiliation(s)
- Hameed Al-Sarraf
- Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Slava Malatiali
- Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Mariam Al-Awadi
- Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait
| | - Zoran Redzic
- Department of Physiology, Faculty of Medicine, Kuwait University, Kuwait.
| |
Collapse
|
11
|
Zamanlu M, Farhoudi M, Eskandani M, Mahmoudi J, Barar J, Rafi M, Omidi Y. Recent advances in targeted delivery of tissue plasminogen activator for enhanced thrombolysis in ischaemic stroke. J Drug Target 2017; 26:95-109. [PMID: 28796540 DOI: 10.1080/1061186x.2017.1365874] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Tissue plasminogen activator (tPA) is the only FDA approved medical treatment for the ischaemic stroke. However, it associates with some inevitable limitations, including: short therapeutic window, extremely short half-life and low penetration in large clots. Systemic administration may lead to complications such as haemorrhagic conversion in the brain and relapse in the form of re-occlusion. Furthermore, ultrasound has been utilised in combination with contrast agents, echogenic liposome, microspheres or nanoparticles (NPs) carrying tPA for improving thrombolysis - an approach that has resulted in slight improvement of tPA delivery and facilitated thrombolysis. Most of these delivery systems are able to extend the circulating half-life and clot penetration of tPA. Various technologies employed for ameliorated thrombolytic therapy are in different phases, some are in final steps for clinical applications while some others are under investigations for their safety and efficacy in human cases. Here, recent progresses on the thrombolytic therapy using novel nano- and micro-systems incorporating tPA are articulated. Of these, liposomes and microspheres, polymeric NPs and magnetic nanoparticles (MNPs) are discussed. Key technologies implemented for efficient delivery of tPA and advanced thrombolytic therapy and their advantages/disadvantages are further expressed.
Collapse
Affiliation(s)
- Masumeh Zamanlu
- a Neurosciences Research Center (NSRC), Faculty of Medicine , Tabriz University of Medical Sciences , Tabriz , Iran.,b Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Mehdi Farhoudi
- a Neurosciences Research Center (NSRC), Faculty of Medicine , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Morteza Eskandani
- b Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Javad Mahmoudi
- a Neurosciences Research Center (NSRC), Faculty of Medicine , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Jaleh Barar
- b Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute , Tabriz University of Medical Sciences , Tabriz , Iran.,c Department of Pharmaceutics, Faculty of Pharmacy , Tabriz University of Medical Sciences , Tabriz , Iran
| | - Mohammad Rafi
- d Department of Neurology, Sidney Kimmel College of Medicine , Thomas Jefferson University , Philadelphia , PA , USA
| | - Yadollah Omidi
- b Research Center for Pharmaceutical Nanotechnology, Biomedicine Institute , Tabriz University of Medical Sciences , Tabriz , Iran.,c Department of Pharmaceutics, Faculty of Pharmacy , Tabriz University of Medical Sciences , Tabriz , Iran
| |
Collapse
|
12
|
Sutherland BA, Fordsmann JC, Martin C, Neuhaus AA, Witgen BM, Piilgaard H, Lønstrup M, Couch Y, Sibson NR, Lauritzen M, Buchan AM. Multi-modal assessment of neurovascular coupling during cerebral ischaemia and reperfusion using remote middle cerebral artery occlusion. J Cereb Blood Flow Metab 2017; 37:2494-2508. [PMID: 27629101 PMCID: PMC5531347 DOI: 10.1177/0271678x16669512] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 12/28/2022]
Abstract
Hyperacute changes in cerebral blood flow during cerebral ischaemia and reperfusion are important determinants of injury. Cerebral blood flow is regulated by neurovascular coupling, and disruption of neurovascular coupling contributes to brain plasticity and repair problems. However, it is unknown how neurovascular coupling is affected hyperacutely during cerebral ischaemia and reperfusion. We have developed a remote middle cerebral artery occlusion model in the rat, which enables multi-modal assessment of neurovascular coupling immediately prior to, during and immediately following reperfusion. Male Wistar rats were subjected to remote middle cerebral artery occlusion, where a long filament was advanced intraluminally through a guide cannula in the common carotid artery. Transcallosal stimulation evoked increases in blood flow, tissue oxygenation and neuronal activity, which were diminished by middle cerebral artery occlusion and partially restored during reperfusion. These evoked responses were not affected by administration of the thrombolytic alteplase at clinically used doses. Evoked cerebral blood flow responses were fully restored at 24 h post-middle cerebral artery occlusion indicating that neurovascular dysfunction was not sustained. These data show for the first time that the rat remote middle cerebral artery occlusion model coupled with transcallosal stimulation provides a novel method for continuous assessment of hyperacute neurovascular coupling changes during ischaemia and reperfusion, and offers unique insight into hyperacute ischaemic pathophysiology.
Collapse
Affiliation(s)
- Brad A Sutherland
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- School of Medicine, Faculty of Health, University of Tasmania, Hobart, Australia
| | - Jonas C Fordsmann
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Chris Martin
- Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
- Department of Psychology, The University of Sheffield, Sheffield, UK
| | - Ain A Neuhaus
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Brent M Witgen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Henning Piilgaard
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Micael Lønstrup
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Yvonne Couch
- Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Nicola R Sibson
- Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Martin Lauritzen
- Department of Neuroscience and Pharmacology, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Neurophysiology, Glostrup Hospital, Glostrup, Denmark
| | | |
Collapse
|
13
|
Neuhaus AA, Couch Y, Hadley G, Buchan AM. Neuroprotection in stroke: the importance of collaboration and reproducibility. Brain 2017. [DOI: 10.1093/brain/awx126] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Ain A Neuhaus
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Yvonne Couch
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Gina Hadley
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Alastair M Buchan
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Medical Sciences Division, University of Oxford, Oxford, UK
- Acute Vascular Imaging Centre, University of Oxford, Oxford University Hospitals, Oxford, UK
| |
Collapse
|
14
|
Dong MX, Hu QC, Shen P, Pan JX, Wei YD, Liu YY, Ren YF, Liang ZH, Wang HY, Zhao LB, Xie P. Recombinant Tissue Plasminogen Activator Induces Neurological Side Effects Independent on Thrombolysis in Mechanical Animal Models of Focal Cerebral Infarction: A Systematic Review and Meta-Analysis. PLoS One 2016; 11:e0158848. [PMID: 27387385 PMCID: PMC4936748 DOI: 10.1371/journal.pone.0158848] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Accepted: 06/22/2016] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND AND PURPOSE Recombinant tissue plasminogen activator (rtPA) is the only effective drug approved by US FDA to treat ischemic stroke, and it contains pleiotropic effects besides thrombolysis. We performed a meta-analysis to clarify effect of tissue plasminogen activator (tPA) on cerebral infarction besides its thrombolysis property in mechanical animal stroke. METHODS Relevant studies were identified by two reviewers after searching online databases, including Pubmed, Embase, and ScienceDirect, from 1979 to 2016. We identified 6, 65, 17, 12, 16, 12 and 13 comparisons reporting effect of endogenous tPA on infarction volume and effects of rtPA on infarction volume, blood-brain barrier, brain edema, intracerebral hemorrhage, neurological function and mortality rate in all 47 included studies. Standardized mean differences for continuous measures and risk ratio for dichotomous measures were calculated to assess the effects of endogenous tPA and rtPA on cerebral infarction in animals. The quality of included studies was assessed using the Stroke Therapy Academic Industry Roundtable score. Subgroup analysis, meta-regression and sensitivity analysis were performed to explore sources of heterogeneity. Funnel plot, Trim and Fill method and Egger's test were obtained to detect publication bias. RESULTS We found that both endogenous tPA and rtPA had not enlarged infarction volume, or deteriorated neurological function. However, rtPA would disrupt blood-brain barrier, aggravate brain edema, induce intracerebral hemorrhage and increase mortality rate. CONCLUSIONS This meta-analysis reveals rtPA can lead to neurological side effects besides thrombolysis in mechanical animal stroke, which may account for clinical exacerbation for stroke patients that do not achieve vascular recanalization with rtPA.
Collapse
Affiliation(s)
- Mei-Xue Dong
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Neurobiology, Chongqing, China
| | - Qing-Chuan Hu
- Chongqing Key Laboratory of Neurobiology, Chongqing, China
| | - Peng Shen
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jun-Xi Pan
- Chongqing Key Laboratory of Neurobiology, Chongqing, China
| | - You-Dong Wei
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yi-Yun Liu
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yi-Fei Ren
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zi-Hong Liang
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hai-Yang Wang
- Chongqing Key Laboratory of Neurobiology, Chongqing, China
| | - Li-Bo Zhao
- Department of Neurology, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
| | - Peng Xie
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Institute of Neuroscience and the Collaborative Innovation Center for Brain Science, Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Neurobiology, Chongqing, China
- * E-mail:
| |
Collapse
|
15
|
Sutherland BA, Neuhaus AA, Couch Y, Balami JS, DeLuca GC, Hadley G, Harris SL, Grey AN, Buchan AM. The transient intraluminal filament middle cerebral artery occlusion model as a model of endovascular thrombectomy in stroke. J Cereb Blood Flow Metab 2016; 36:363-9. [PMID: 26661175 PMCID: PMC4759672 DOI: 10.1177/0271678x15606722] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 08/19/2015] [Indexed: 01/10/2023]
Abstract
The clinical relevance of the transient intraluminal filament model of middle cerebral artery occlusion (tMCAO) has been questioned due to distinct cerebral blood flow profiles upon reperfusion between tMCAO (abrupt reperfusion) and alteplase treatment (gradual reperfusion), resulting in differing pathophysiologies. Positive results from recent endovascular thrombectomy trials, where the occluding clot is mechanically removed, could revolutionize stroke treatment. The rapid cerebral blood flow restoration in both tMCAO and endovascular thrombectomy provides clinical relevance for this pre-clinical model. Any future clinical trials of neuroprotective agents as adjuncts to endovascular thrombectomy should consider tMCAO as the model of choice to determine pre-clinical efficacy.
Collapse
Affiliation(s)
- Brad A Sutherland
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Ain A Neuhaus
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Yvonne Couch
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Joyce S Balami
- Centre for Evidence Based Medicine, University of Oxford, Oxford, UK Norfolk and Norwich University Teaching Hospital NHS Trust, Norwich, UK
| | - Gabriele C DeLuca
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Gina Hadley
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Scarlett L Harris
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Adam N Grey
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Alastair M Buchan
- Acute Stroke Programme, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
16
|
Moretti A, Ferrari F, Villa RF. Pharmacological therapy of acute ischaemic stroke: Achievements and problems. Pharmacol Ther 2015; 153:79-89. [DOI: 10.1016/j.pharmthera.2015.06.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 06/03/2015] [Indexed: 01/04/2023]
|
17
|
Wei X, Zhang B, Cheng L, Chi M, Deng L, Pan H, Yao X, Wang G. Hydrogen sulfide induces neuroprotection against experimental stroke in rats by down-regulation of AQP4 via activating PKC. Brain Res 2015; 1622:292-9. [PMID: 26168888 DOI: 10.1016/j.brainres.2015.07.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 06/22/2015] [Accepted: 07/03/2015] [Indexed: 12/23/2022]
Abstract
Hydrogen sulfide (H2S) is now known as an important neuromodulator in the central nervous system. The aim of the current study was to investigate whether exogenous H2S gas can attenuate brain edema induced by experimental stroke and to clarify the potential mechanisms. Rats underwent 2-h middle cerebral artery occlusion (MCAO) and received 40 ppm or 80 ppm H2S inhalation for 3h at the beginning of reperfusion. The effects of H2S were investigated by evaluating neurological function, infarct size, brain edema volume, and aquaporin4 (AQP4) protein expression at 24h after reperfusion. Moreover, to explore the possible mechanisms for the neuroprotective effects of H2S, protein kinase C (PKC) activity was detected and a PKC inhibitor, Go6983, was used via intracerebral ventricular injection. Our results showed that 40 ppm or 80 ppm H2S inhalation significantly reduced neurological deficits, infarct size, and brain edema after MCAO. The expression of AQP4 in the peri-infarct area of brain was also inhibited after inhalation of H2S. PKC was activated by H2S treatment and the PKC inhibitor attenuated the neuroprotection of H2S with an increased AQP4 expression at the same time. In conclusion, H2S inhalation attenuates brain edema, reduces infarct volume, and improves neurologic function in a rat experimental stroke model. The therapeutic benefits of H2S inhalation are associated with down-regulation of AQP4 expression via activating PKC.
Collapse
Affiliation(s)
- Xia Wei
- Department of Anesthesiology, Cancer Hospital Affiliated to Harbin Medical University, 150 Haping Road, Harbin, Heilongjiang 150081, China
| | - Bing Zhang
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Harbin, Heilongjiang 150086, China
| | - Long Cheng
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Harbin, Heilongjiang 150086, China
| | - Meng Chi
- Department of Anesthesiology, Cancer Hospital Affiliated to Harbin Medical University, 150 Haping Road, Harbin, Heilongjiang 150081, China
| | - Lin Deng
- Department of Anesthesiology, Cancer Hospital Affiliated to Harbin Medical University, 150 Haping Road, Harbin, Heilongjiang 150081, China
| | - Hong Pan
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Harbin, Heilongjiang 150086, China
| | - Xuan Yao
- Department of Anesthesiology, Second Affiliated Hospital of Harbin Medical University, 246 Xuefu Road, Harbin, Heilongjiang 150086, China
| | - Guonian Wang
- Department of Anesthesiology, Cancer Hospital Affiliated to Harbin Medical University, 150 Haping Road, Harbin, Heilongjiang 150081, China.
| |
Collapse
|