scholarly journals PKA-Dependent Membrane Surface Recruitment of CI-AMPARs Is Crucial for BCP-Mediated Protection Against Post-acute Ischemic Stroke Cognitive Impairment

2020 ◽  
Vol 11 ◽  
Author(s):  
Sha Chen ◽  
Yuchun Wang ◽  
Xuhui Wang ◽  
Meng He ◽  
Lu Zhang ◽  
...  

Post-acute ischemic stroke cognitive impairment frequently occurs and seriously affects patients daily activities. Recruitment of GluA2-containing Ca2+-impermeable AMPA receptors (CI-AMPARs) to hippocampal synaptic membrane surfaces was shown to trigger synaptic plasticity. Currently, the effect of CI-AMPAR trafficking on acute ischemic stroke remains poorly understood. β-Caryophyllene (BCP) has been shown to ameliorate cognitive impairment. However, the mechanism has not been characterized. In this study, a 60-min temporary middle cerebral artery occlusion (MCAO) model was established to simulate the pathology of acute ischemic stroke. BCP reduced neurologic deficits, cerebral infarct volume, and pathological damage in MCAO mice and caused CI-AMPARs to translocate to synaptic membranes in the hippocampus; surface expression of CI-AMPARs was also decreased in MCAO mice. Furthermore, this study also showed that BCP treatment significantly activated the cAMP/PKA pathway, which is consistent with the synaptic membrane expression of CI-AMPARs. To better understand the underlying mechanisms, the PKA inhibitor H-89 was used to study the role of BCP in MCAO mice. Interestingly, H-89 treatment significantly disrupted the BCP-mediated facilitation of CI-AMPAR translocation to the synaptic membrane surface and substantially attenuated BCP-induced protection against acute ischemic stroke. Additionally, inhibition the cAMP/PKA pathway not only reduced BCP-induced inhibition of AMPAR-mediated excitatory postsynaptic currents in the hippocampal CA1 region but also decreased the effect of BCP-mediated protection against post-acute ischemic stroke cognitive impairment. Taken together, these data indicate that PKA-dependent synaptic membrane surface recruitment of CI-AMPARs is crucial for the neuroprotective effect of BCP against acute ischemic stroke and protection against post-acute ischemic stroke cognitive impairment.

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Xiaokun Geng ◽  
Xunming Ji ◽  
Fei Wang ◽  
Yu Wang ◽  
Karam ASMARO ◽  
...  

Background and Purpose _ Despite a focus on the pathological effects of alcohol abuse, numerous studies published over the past several decades also demonstrate beneficial effects of light-to-moderate consumption of alcoholic beverages. Recent studies have demonstrated that elevated serum ethanol levels are associated with increased survival in patients with traumatic brain injury (TBI), suggesting that an acute exposure to alcohol exerts a neuroprotective effect. In a rat model of transient cerebral ischemia, we identified administration of ethanol as a possible treatment for acute ischemic stroke. Methods _Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for two hours. Five sets of experiments were conducted: 1) to determine the dose-response effect of ethanol (0.5, 1.0 and 1.5g/kg) on brain infarction and functional outcome; 2) to determine whether combining ethanol (1.5g/kg) and hypothermia produces synergistic neuroprotection; 3) to determine the therapeutic windows of opportunity for ethanol in stroke; to test whether ethanol promotes intracerebral hemorrhage (ICH) in hemorrhagic or ischemic stroke, or after administration of thrombolytics in ischemic stroke; and 5) to test the affect of ethanol on HIF-1α protein expression. Results —Ethanol at 1.5 g/kg, which produce blood levels (89mg/dL) within the legally intoxicated range for driving (80-100 g/dL), most effectively reduced infarct volume and behavioral dysfunction when administered at 2, 3 or 4 hours after MCAO. We find that ethanol and moderate hypothermia (32-34 °C) exert neuroprotective effects of similar magnitude at both the lesion volume and functional levels, but do not exert a synergistic effect in this model. Ethanol did not promote cerebral hemorrhage in hemorrhagic or ischemic stroke in combination with recombinant tissue plasminogen activator (rt-PA) or urokinase (UK). Up-regulation of HIF-1α protein levels was enhanced by ethanol, in association with reduced brain infarct volume and improved functional recovery in rats subjected to stroke using the same dose (1.5 g/kg). Conclusions —Ethanol exerts a strong neuroprotective effect when administered up to 4 hours after ischemia, and does not promote ICH when used with thrombolytics. Ethanol is a potential neuroprotectant for acute ischemic stroke.


2017 ◽  
Vol 44 (1-2) ◽  
pp. 88-95 ◽  
Author(s):  
Rolf A. Blauenfeldt ◽  
Kristina D. Hougaard ◽  
Kim Mouridsen ◽  
Grethe Andersen

Background: A high prestroke physical activity (PA) level is associated with reduced stroke rate, stroke mortality, better functional outcome, and possible neuroprotective abilities. The aim of the present study was to examine the possible neuroprotective effect of prestroke PA on 24-h cerebral infarct growth in a cohort of acute ischemic stroke patients treated with intravenous tPA and randomized to remote ischemic perconditioning. Methods: In this predefined subanalysis, data from a randomized clinical trial investigating the effect of remote ischemic perconditioning (RIPerC) on AIS was used. Prestroke (7 days before admission) PA was quantified using the PA Scale for the Elderly (PASE) questionnaire at baseline. Infarct growth was evaluated using MRI (acute, 24-h, and 1-month). Results: PASE scores were obtained from 102 of 153 (67%) patients with a median (interquartile range) age of 66 (58-73) years. A high prestroke PA level correlated significantly with reduced acute infarct growth (24 h) in the linear regression model (4th quartile prestroke PA level compared with the 1st quartile), β4th quartile = -0.82 (95% CI -1.54 to -0.10). However, the effect of prestroke PA was present mainly in patients randomized to RIPerC, β4th quartile = -1.14 (95% CI -2.04 to -0.25). In patients randomized to RIPerC, prestroke PA was a predictor of final infarct size (1-month infarct volume), β4th quartile = -1.78 (95% CI -3.15 to -0.41). Conclusion: In AIS patients treated with RIPerC, as add-on to intravenous thrombolysis, the level of PA the week before the stroke was associated with decreased 24-h infarct growth and final infarct size. These results are highly encouraging and stress the need for further exploration of the potentially protective effects of both PA and remote ischemic conditioning.


2021 ◽  
Vol 12 ◽  
Author(s):  
Haiting An ◽  
Wuhai Tao ◽  
Ying Liang ◽  
Peng Li ◽  
Min Li ◽  
...  

Acute ischemic stroke (AIS) is a global health burden and cognitive impairment is one of its most serious complication. Adequate interventions for AIS may have the potential to improve cognitive outcomes. In the present study, we selected Erigeron breviscapus (Vaniot) Hand.-Mazz. injection (Dengzhanxixin injection, DZXI), a widely used Chinese herbal injection, in contrast to edaravone as the positive control drug to test its potential to ameliorates neurological and cognitive impairments caused by AIS. We performed a 2-week randomized trial with these two drugs in AIS patients presenting mild to moderate cognitive impairments. Neuropsychological tests and MRI examinations showed that DZXI attenuated the neurological and cognitive impairments of patients and protected the grey matter in specific regions from ischemic damage. Notably, DZXI exerted better effects than edaravone in some neuropsychological tests, probably due to the protective effect of DZXI on grey matter. To explore the therapeutic mechanisms, we carried out an experiment with a middle cerebral artery occlusion rat model. We found that DZXI decreased the infarct volume and increased the survival of neuronal cells in the ischemic penumbra; furthermore, DZXI modulated the mitochondrial respiratory chain process and preserved the mitochondrial structure in the brain tissue. Overall, our data suggested that the administration of DZXI is effective at ameliorating neurological and cognitive impairments in AIS, and the underlying mechanisms are related to the protective effects of DZXI on cerebral neurons and neuronal mitochondria.


2021 ◽  
pp. 0271678X2199298
Author(s):  
Chao Li ◽  
Chunyang Wang ◽  
Yi Zhang ◽  
Owais K Alsrouji ◽  
Alex B Chebl ◽  
...  

Treatment of patients with cerebral large vessel occlusion with thrombectomy and tissue plasminogen activator (tPA) leads to incomplete reperfusion. Using rat models of embolic and transient middle cerebral artery occlusion (eMCAO and tMCAO), we investigated the effect on stroke outcomes of small extracellular vesicles (sEVs) derived from rat cerebral endothelial cells (CEC-sEVs) in combination with tPA (CEC-sEVs/tPA) as a treatment of eMCAO and tMCAO in rat. The effect of sEVs derived from clots acquired from patients who had undergone mechanical thrombectomy on healthy human CEC permeability was also evaluated. CEC-sEVs/tPA administered 4 h after eMCAO reduced infarct volume by ∼36%, increased recanalization of the occluded MCA, enhanced cerebral blood flow (CBF), and reduced blood-brain barrier (BBB) leakage. Treatment with CEC-sEVs given upon reperfusion after 2 h tMCAO significantly reduced infarct volume by ∼43%, and neurological outcomes were improved in both CEC-sEVs treated models. CEC-sEVs/tPA reduced a network of microRNAs (miRs) and proteins that mediate thrombosis, coagulation, and inflammation. Patient-clot derived sEVs increased CEC permeability, which was reduced by CEC-sEVs. CEC-sEV mediated suppression of a network of pro-thrombotic, -coagulant, and -inflammatory miRs and proteins likely contribute to therapeutic effects. Thus, CEC-sEVs have a therapeutic effect on acute ischemic stroke by reducing neurovascular damage.


Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Takuya Kanamaru ◽  
Satoshi Suda ◽  
Junya Aoki ◽  
Kentaro Suzuki ◽  
Yuki Sakamoto ◽  
...  

Background: It is reported that pre-stroke cognitive impairment is associated with poor functional outcome after stroke associated with small vessel disease. However, it is not clear that pre-stroke cognitive impairment is associated with poor outcome in patients treated with mechanical thrombectomy. Method: We enrolled 127 consecutive patients treated with mechanical thrombectomy for acute ischemic stroke from December 2016 to November 2018. Pre-stroke cognitive function was evaluated using the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). We retrospectively compared poor outcome (a score of 3 to 6 on the modified Rankin Scale at 90 days) group (n=75) with good outcome (a score of 0, 1, or 2 on the modified Rankin Scale at 90 days) group (n=52) and examined that IQCODE could be the predictor of PO. Result: IQCODE was significantly higher in poor outcome group than in good outcome group (89 vs. 82, P=0.0012). Moreover, age (77.2 years old vs. 71.6 years old, P= 0.0009), the percentage of female (42.7% vs. 17.3%, P= 0.0021), complication of hypertension (HT, 68.0% vs. 44.2%, P=0.0076), National Institutes of Health Stroke Scale (NIHSS) at admission (20 vs. 11, P<0.0001), the percentage of postoperative intracerebral hemorrhage (ICH, 33.3% vs. 15.4%, P=0.0233) were higher in poor outcome group than in good outcome group, too. However, there was no significant difference between poor outcome and good outcome groups in occlusion site (P= 0.1229), DWI-ASPECTS (P= 0.2839), the duration from onset to recanalization (P=0.4871) and other risk factors. Multivariable logistic regression analysis demonstrated that IQCODE, HT and NIHSS at admission were associated with poor outcome (P= 0.0128, P=0.0061 and P<0.0001, respectively). Conclusion: Cognitive impairment could be associated with poor outcome in patients treated with mechanical thrombectomy.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Johanna Ospel ◽  
Michael D Hill ◽  
Nima Kashani ◽  
Arnuv Mayank ◽  
Nishita Singh ◽  
...  

Purpose: We investigated the prevalence and prognostic impact on outcome of any intracranial hemorrhage, hemorrhage morphology, type and volume in acute ischemic stroke patients undergoing mechanical thrombectomy. Methods: Prevalence of intracranial hemorrhage, hemorrhage type, morphology and volume was determined on 24h follow-up imaging (non contrast head CT or gradient-echo/susceptibility-weighted MRI). Proportions of good outcome (mRS 0-2 at 90 days) were reported for patients with vs. without any intracranial hemorrhage. Multivariable logistic regression with adjustment for key minimization variables and total infarct volume was performed to obtain adjusted effect size estimates for hemorrhage type and volume on good outcome. Results: Hemorrhage on follow up-imaging was seen in 372/1097 (33.9%) patients, among them 126 (33.9%) with hemorrhagic infarction (HI) type 1, 108 (29.0%) with HI-2, 72 /19.4%) with parenchymal hematoma (PH) type 1, 37 (10.0) with PH2, 8 (2.2%) with remote PH and 21 (5.7%) with extra-parenchymal/intraventricular hemorrhage. Good outcomes were less often achieved by patients with hemorrhage on follow-up imaging (164/369 [44.4%] vs. 500/720 [69.4%]). Any type of intracranial hemorrhage was strongly associated with decreased chances of good outcome ( adj OR 0.62 [CI 95 0.44 - 0.87]). The effect of hemorrhage was driven by both PH hemorrhage sub-type [PH-1 ( adj OR 0.39 [CI 95 0.21 - 0.72]), PH-2 ( adj OR 0.15 [CI 95 0.05 - 0.50])] and extra-parenchymal/intraventricular hemorrhage ( adj OR 0.60 (0.20-1.78) Petechial hemorrhages (HI-1 and HI-2) were not associated with poorer outcomes. Hemorrhage volume ( adj OR 0.97 [CI 95 0.05 - 0.99] per ml increase) was significantly associated with decreased chances of good outcome. Conclusion: Presence of any hemorrhage on follow-up imaging was seen in one third of patients and strongly associated with decreased chances of good outcome.


Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Sweena Parmar ◽  
Xiaokun Geng ◽  
Changya Peng ◽  
Murali Guthikonda ◽  
Yuchuan Ding

Objectives: Normobaric oxygenation (NBO) has been shown to provide neuroprotection in vivo and in vitro . Yet, a recent Phase 2 clinical trial investigating NBO therapy in acute ischemic stroke was terminated due to questionable therapeutic benefit. NBO therapy alone may be insufficient to produce improved outcomes. In our recent study, we demonstrated a strong neuroprotective effect of ethanol at a dose of 1.5 g/kg (equivalent to the human legal driving limit). In this study, we sought to identify whether low-dose ethanol administration enhances the neuroprotection offered by NBO and whether combined administration of NBO with ethanol is associated with reduced apoptosis. Methods: Sprague-Dawley rats were subjected to right middle cerebral artery occlusion (MCAO) for 2 h, followed by reperfusion. Ischemic animals received either an intraperitoneal injection of 1.0 g/kg ethanol, 2 h of 100% NBO, or both ethanol and NBO. The Cell Death Detection ELISA Assay (Roche) was performed to determine apoptotic cell death at 24 h after reperfusion. Levels of pro-apoptotic (Caspase-3, Bcl-2-associated X-BAX, and Apoptosis-Inducing Factor-AIF) and anti-apoptotic proteins (Bcl-2 and Bcl-xL) were determined by Western blot analysis at 3 and 24 h after reperfusion. Results: As expected, untreated ischemic rats had the highest apoptotic cell death. Combined NBO/ethanol therapy decreased cell death by 48%, as compared to 29% with ethanol and 22% with NBO. Similarly, combined NBO/ethanol therapy promoted the greatest expression of anti-apoptotic factors and the lowest expression of pro-apoptotic proteins at 3 h after reperfusion. This effect was maintained at 24 h and even more pronounced for AIF and Caspase-3. Conclusions: Given singularly, NBO and ethanol improved the degree of cell death, decreased the expression of pro-apoptotic proteins, and increased the expression of anti-apoptotic proteins. Yet, when administered together, their effects largely compounded. These results suggest a synergistic neuroprotection offered by NBO with ethanol, which may be attributed at least in part to their shared role in modulating neuronal apoptosis.


Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
H. B Brouwers ◽  
Svetlana Lorenzano ◽  
Lyndsey H Starks ◽  
David M Greer ◽  
Steven K Feske ◽  
...  

Purpose: Hemorrhagic transformation (HT) is a common and potentially devastating complication of ischemic stroke, however its prevalence, predictors, and outcome remain unclear. Early anticoagulation is thought to be a risk factor for HT which raises the clinical question when to (re)start anticoagulation in ischemic stroke patients who have a compelling indication, such as atrial fibrillation. We conducted a prospective cohort study to address this question and to identify association of hemorrhagic transformation with outcome measures in patients with atrial fibrillation in the setting of acute ischemic stroke. Materials and Methods: We performed a prospective study which enrolled consecutive patients admitted with acute ischemic stroke presenting to a single center over a three-year period. As part of the observational study, baseline clinical data and stroke characteristics as well as 3 month functional outcome were collected. For this sub-study, we restricted the analysis to subjects diagnosed with atrial fibrillation. CT and MRI scans were reviewed by experienced readers, blinded to clinical data, to assess for hemorrhagic transformation (using ECASS 2 criteria), microbleeds and infarct volumes in both admission and follow-up scans. Clinical and outcome data were analyzed for association with hemorrhagic transformation. Results: Of 94 patients, 63 had a history of atrial fibrillation (67.0%) and 31 had newly discovered atrial fibrillation (33.0%). We identified HT in 3 of 94 baseline scans (3.2%) and 22 of 48 follow-up scans (45.8%) obtained a median of 3 days post-stroke. In-hospital initiation of either anti-platelet (n = 36; OR 0.34 [95% CI 0.10-1.16], p-value = 0.09) or anticoagulation with unfractionated intravenous heparin or low molecular weight heparin (n = 72; OR 0.25 [95% CI 0.06-1.15], p-value = 0.08) was not associated with HT. Initial NIH Stroke Scale (NIHSS) score (median 13.0 [IQR 15.0] vs. 7.0 [IQR 10.0], p-value = 0.029) and baseline infarct volume (median 17 [IQR 42.03] vs. 5 [IQR 10.95], p-value = 0.011) were significantly higher in patients with HT compared to those without. Hemorrhagic transformation was associated with a significantly higher 48-hour median NIHSS score (20 [IQR 3.0] vs. 2 [IQR 3.25], p-value = 0.007) and larger final infarct volume (81.40 [IQR 82.75] vs. 9.95 [IQR 19.73], p-value < 0.001). Finally, we found a trend towards poorer 3-month modified Rankin Scale scores in subjects with HT (OR 11.25 [95% CI 0.97-130.22], p-value = 0.05). Conclusion: In patients with atrial fibrillation, initial NIHSS score and baseline infarct volume are associated with hemorrhagic transformation in acute ischemic stroke. Early initiation of antithrombotic therapy was not associated with hemorrhagic transformation. Patients with hemorrhagic transformation were found to have a poorer short and long term outcome and larger final infarct volumes.


Author(s):  
Ani Kartini ◽  
Mansyur Arif ◽  
Hardjoeno Hardjoeno

Coagulation activation and thrombosis frequently exist in ischemic stroke, thrombus formation can be detected early by the presence of fibrin monomer. The purpose of this study was to know the correlation of fibrin monomer level with cerebral infarct size in acute ischemic stroke patients. This was a cross sectional study with a total of 39 samples. The fibrin monomer level was determined by immunoturbidimetry method using STA-Compact and the measurement of the infarct size was done by CT scan of the head using Broderick formula. The results of this study showed that the median level of fibrin monomer in acute ischemic stroke with nonlacunar infarct type and lacunar infarct type were 14.46 μg/mL and 4.29 μg/mL, respectively. Mann-Whitney test showed there was a significant difference of fibrin monomer levels between nonlacunar infarct type and the lacunar type, p=0.000. The cut-off point analysis result of the fibrin monomer level was 5.96 μg/mL with a sensitivity of 88.9% and specificity of 76.4%, respectively. Spearman correlation test showed that fibrin monomer level was positively correlated with cerebral infarct volume in acute ischemic stroke (r=0.56, p=0.000). Based on this study, it can be concluded that fibrin monomer level can be used as a marker to predict the type of cerebral infarct and volume of acute ischemic stroke as well.


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