Angiography-based hemodynamic features predict recurrent ischemic events after angioplasty and stenting of intracranial vertebrobasilar atherosclerotic stenosis.

OBJECTIVES: To assess the predictive value of hemodynamic features for stroke relapse in patients with intracranial vertebrobasilar atherosclerotic stenosis treated with percutaneous transluminal angioplasty and stenting (PTAS) using quantitative digital subtraction angiography (q-DSA). METHODS: In this retrospective longitudinal study, patients with intracranial vertebrobasilar atherosclerotic stenosis and who underwent PTAS treatment between January 2012 and May 2020 were enrolled. The q-DSA assessment was performed before and after PTAS. ROIs 1-4 were placed along the vertebral artery, proximal and distal basilar artery, and posterior cerebral artery; ROIs 5-8 were in 5 mm and 10 mm proximal and distal to the lesion, respectively. Relative time to peak (rTTP) was defined as the difference in TTP between ROIs. Cox regression analyses were performed to determine risk factors for recurrent stroke. RESULTS: A total of 137 patients (mean age, 62 years ± 10 [standard deviation], 83.2% males) were included, and 26 (19.0%) patients had stroke relapse during follow-up (median time of 42.6 months [interquartile range, 19.7-60.7]). Preprocedural rTTP4-1 (adjusted hazard ratio (HR) = 2.270; 95% CI 1.371-3.758; p = 0.001) and preprocedural rTTP8-5 (adjusted HR = 0.240; 95% CI 0.088-0.658; p = 0.006) were independently associated with the recurrent stroke. These hemodynamic parameters provided an incremental prognostic value for stroke relapse (AUC, 0.817 [0.704-0.931]; the net reclassification index, 0.431 [0.057-0.625]; and the integrated discrimination index, 0.140 [0.035-0.292]). CONCLUSIONS: In patients with intracranial vertebrobasilar atherosclerosis treated with PTAS, preprocedural prolonged TTP of the target vessel and shortened trans-stenotic TTP difference were associated with stroke relapse. Q-DSA-defined hemodynamic parameters provided incremental predictive value over conventional parameters for stroke recurrence. CLINICAL RELEVANCE STATEMENT: Quantitative DSA analysis enables intuitive observation and semi-quantitative evaluation of peri-therapeutic cerebral blood flow. More importantly, quantitative DSA-defined hemodynamic parameters have the potential for risk stratification of patients with intracranial atherosclerotic stenosis. KEY POINTS: Semi-quantitative angiography-based parameters can reflect pre- and postprocedural subtle changes in blood flow in patients with intracranial atherosclerotic stenosis. Although angioplasty procedures can significantly improve blood flow status, patients with more restricted baseline blood flow still show a higher risk of stroke recurrence. Angiography-based hemodynamic features possess prognostic value and can serve as clinical markers to assess stroke risk of patients with intracranial atherosclerotic stenosis.

Extracellular vesicles carrying proinflammatory factors may spread atherosclerosis to remote locations.

Most cells involved in atherosclerosis release extracellular vesicles (EVs), which can carry bioactive substances to downstream tissues via circulation. We hypothesized that EVs derived from atherosclerotic plaques could promote atherogenesis in remote locations, a mechanism that mimics the blood metastasis of cancer. Ldlr gene knockout (Ldlr KO) rats were fed on a high cholesterol diet and underwent partial carotid ligation to induce local atherosclerosis. EVs were separated from carotid artery tissues and downstream blood of carotid ligation by centrifugation. MiRNA sequencing and qPCR were then performed to detect miRNA differences in EVs from rats with and without induced carotid atherosclerosis. Biochemical analyses demonstrated that EVs derived from atherosclerosis could increase the expression of ICAM-1, VCAM-1, and E-selectin in endothelial cells in vitro. EVs derived from atherosclerosis contained a higher level of miR-23a-3p than those derived from controls. MiR-23a-3p could promote endothelial inflammation by targeting Dusp5 and maintaining ERK1/2 phosphorylation in vitro. Inhibiting EV release could attenuate atherogenesis and reduce macrophage infiltration in vivo. Intravenously administrating atherosclerotic plaque-derived EVs could induce intimal inflammation, arterial wall thickening and lumen narrowing in the carotids of Ldlr KO rats, while simultaneous injection of miR-23a-3p antagomir could reverse this reaction. The results suggested that EVs may transfer atherosclerosis to remote locations by carrying proinflammatory factors, particularly miR-23a-3p.

Recognition of Abnormal Chest Compression Depth Using One-Dimensional Convolutional Neural Networks.

When the displacement of an object is evaluated using sensor data, its movement back to the starting point can be used to correct the measurement error of the sensor. In medicine, the movements of chest compressions also involve a reciprocating movement back to the starting point. The traditional method of evaluating the effects of chest compression depth (CCD) is to use an acceleration sensor or gyroscope to obtain chest compression movement data; from these data, the displacement value can be calculated and the CCD effect evaluated. However, this evaluation procedure suffers from sensor errors and environmental interference, limiting its applicability. Our objective is to reduce the auxiliary computing devices employed for CCD effectiveness evaluation and improve the accuracy of the evaluation results. To this end, we propose a one-dimensional convolutional neural network (1D-CNN) classification method. First, we use the chest compression evaluation criterion to classify the pre-collected sensor signal data, from which the proposed 1D-CNN model learns classification features. After training, the model is used to classify and evaluate sensor signal data instead of distance measurements; this effectively avoids the influence of pressure occlusion and electromagnetic waves. We collect and label 937 valid CCD results from an emergency care simulator. In addition, the proposed 1D-CNN structure is experimentally evaluated and compared against other CNN models and support vector machines. The results show that after sufficient training, the proposed 1D-CNN model can recognize the CCD results with an accuracy rate of more than 95%. The execution time suggests that the model balances accuracy and hardware requirements and can be embedded in portable devices.

CD99 mediates neutrophil transmigration through the bEnd.3 monolayer via the induction of oxygen-glucose deprivation.

AIM/BACKGROUND: CD99 participate in neutrophil infiltration after inflammatory events; however, despite the important role of inflammation in ischemic stroke, the role of CD99 in ischemic stroke remains unclear. METHOD: In the present study, we detected the protein expression of CD99, ICAM-1, and CD31 (PECAM-1) in oxygen-glucose deprivation (OGD)-induced bEnd.3 cells and neutrophils and explored the influence of HIF-1α and IL-1ß on their expression. We also explored the role of CD99 in the OGD-induced transmigration of neutrophils. RESULTS: Our results showed that OGD induction upregulated CD99 in bEnd.3 cells and that this effect could be abolished by the preadministration of IL-1ß and was not mediated by HIF-1α. However, the activation of ICAM-1 by OGD remained activated with IL-1ß treatment. No significant influence of IL-1ß on OGD-induced CD31. Finally, we found a significant increase in infiltrated neutrophils after OGD induction compared with the control and OGD + anti-CD99 groups. CONCLUSION: Our results indicated that CD99 mediates neutrophil infiltration and transmigration via OGD induction and thus constitutes a potential therapeutic target for anti-inflammatory treatment after ischemic stroke.

Cholesterol Crystals are Associated with Carotid Plaque Vulnerability: An Optical Coherence Tomography Study.

OBJECTIVE: Vulnerable carotid plaque is associated with cerebrovascular events. Cholesterol crystals are often seen in the atherosclerotic plaques. However, the potential role of cholesterol crystals in carotid plaques destabilization is unknown. We aimed to identify the association between cholesterol crystals and carotid plaque vulnerability. METHODS: Optical coherence tomography assessment of carotid plaque was performed in 95 patients. Clinical characteristics and plaque morphology were examined. The differences in plaque characteristics (thrombus, calcification, neovascularization, and macrophage accumulations) and clinical parameters (age, symptom, coronary heart disease, total cholesterol, triglycerides, and C-reactive protein) between patients with or without cholesterol crystals were analyzed with multivariate logistic regression. RESULTS: Among 66 patients with acceptable carotid atherosclerotic optical coherence tomography images, 16 were with and 50 were without cholesterol crystals. 56.3% patients (9 of 16) with cholesterol crystals had cerebrovascular ischemic symptom related to ipsilateral internal carotid artery, whereas only 26.0% patients (13 of 50) without cholesterol crystals had symptom (OR, 3.66; 95% CI, 1.13-11.82; P = .025). 75.0% of the plaques with cholesterol crystals had concomitant macrophage accumulation (OR, 4.14; 95% CI, 1.17-14.65; P = .04). In segments with cholesterol crystals, a higher presence of calcification could be demonstrated compared to those without cholesterol crystals (62.5% versus 32.0%, P = .03). 70.0% plaques with cholesterol crystals and calcification were classified as symptomatic plaques (OR, 6.38; 95% CI, 1.46-27.91; P = .01). No association between plaque rupture and cholesterol crystals was identified. Multivariate logistic regression showed that age and macrophage accumulation were independently associated with cholesterol crystals. CONCLUSIONS: Carotid atherosclerotic plaques with cholesterol crystals were more likely to have concomitant macrophage and calcification accumulations. Patients with cholesterol crystals plaque experienced more cerebrovascular symptoms. Thus, cholesterol crystals, especially together with macrophage and calcification, may serve as an important component of venerable carotid plaques.

Human albumin attenuates excessive innate immunity via inhibition of microglial Mincle/Syk signaling in subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a devastating subtype of stroke. Microglial macrophage-inducible C-type lectin (Mincle) receptor launches microglial innate immunity after SAH, and thereby achieves a key step of early cerebral injury in SAH. We previously revealed albumin could improve long-term neurological outcomes after SAH. In this study, we examined the role of microglia-mediated innate immunity in the salutary effects of albumin. SAH was induced by endovascular perforation in rats. We found that albumin can significantly mitigate early neurovascular dysfunction of SAH rats. Albumin administration resulted in reduced Iba-1 and CD68 staining in cortex. Markers of microglia M1 polarization (iNOS, IL-1ß, CD16, and CD32) were remarkably suppressed. Neutrophil invasion was inhibited as chemokines (MCP-1, CINC-1, and CXCL-2) mRNA levels, myeloperoxidase (MPO) and intracellular adhesion molecule-1 (ICAM-1) expressions were decreased. Mechanistically, albumin bound with microglial Mincle receptor, and retarded Mincle/Syk/IL-1ß signaling in ipsilateral hemisphere subjected to SAH. In the cultured BV-2 microglial cells, we found Mincle and its ligand SAP130 mediate the cross-talk between neuronal necroptosis and microglial immunity response following SAH-related injury. Albumin could attenuate SAP130-induced Mincle upregulation and subsequent microglial inflammatory responses. The anti-inflammation effect of albumin was similar to the effect of genetic knockdown of Mincle. This effect may be attributed to a direct association between albumin and Mincle. The interaction also yielded a depression in the initiation of Mincle/Syk/IL-1ß pathway. In conclusion, our results indicate that albumin can ameliorate innate immune responses after SAH. This anti-inflammatory action may be through direct restraining microglial Mincle receptor.

Caveolin-1 is a checkpoint regulator in hypoxia-induced astrocyte apoptosis via Ras/Raf/ERK pathway.

Astrocytes, the most numerous cells in the human brain, play a central role in the metabolic homeostasis following hypoxic injury. Caveolin-1 (Cav-1), a transmembrane scaffolding protein, has been shown to converge prosurvival signaling in the central nerve system. The present study aimed to investigate the role of Cav-1 in the hypoxia-induced astrocyte injury. We also examined how Cav-1 alleviates apoptotic astrocyte death. To this end, primary astrocytes were exposed to oxygen-glucose deprivation (OGD) for 6 h and a subsequent 24-h reoxygenation to mimic hypoxic injury. OGD significantly reduced Cav-1 expression. Downregulation of Cav-1 using Cav-1 small interfering RNA dramatically worsened astrocyte cell damage and impaired cellular glutamate uptake after OGD, whereas overexpression of Cav-1 with Cav-1 scaffolding domain peptide attenuated OGD-induced cell apoptosis. Mechanistically, the expressions of Ras-GTP, phospho-Raf, and phospho-ERK were sequestered in Cav-1 small interfering RNA-treated astrocytes, yet were stimulated after supplementation with caveolin peptide. MEK/ERK inhibitor U0126 remarkably blocked the Cav-1-induced counteraction against apoptosis following hypoxia, indicating Ras/Raf/ERK pathway is required for the Cav-1's prosurvival role. Together, these findings support Cav-1 as a checkpoint for the in hypoxia-induced astrocyte apoptosis and warrant further studies targeting Cav-1 to treat hypoxic-ischemic brain injury.

Opposite roles of bradykinin B1 and B2 receptors during cerebral ischaemia-reperfusion injury in experimental diabetic rats.

Bradykinin receptors play important roles in cerebral ischaemia-reperfusion (I/R) injury of non-diabetics. Their functions in diabetics, however, have not been studied. In this study, we hypothesized that bradykinin 1 receptor (B1R) and bradykinin 2 receptor (B2R) would be upregulated and participate in the regulation of diabetic ischaemic stroke. To investigate this, we first evaluated B1R and B2R expression at different time points after I/R in non-diabetic and diabetic rats (Sprague-Dawley) by using real-time quantitative reverse transcription polymerase chain reaction, western blotting, and immunofluorescence. Then, pharmacological inhibitors were separately administered via the tail vein to analyse their effects on cerebral ischaemia in diabetics. Both receptors were significantly upregulated after cerebral I/R in non-diabetic and diabetic rats. B1R expression in diabetic rats increased in a sharper manner than in non-diabetic rats, whereas B2R expression increased to the same level during the early stage of reperfusion but later became lower. Interestingly, the upregulated B1R was expressed in astrocytes, whereas B2R was mainly located in neurons in the ischaemic penumbra. Functional studies showed that inhibition of B1R significantly reduced infarct volume, neurological deficits, cell apoptosis, and neuron degeneration, probably by attenuating blood-brain barrier (BBB) disruption and post-ischaemic inflammation, at 24 h after reperfusion. In contrast, B2R antagonist had opposite effects, and exacerbated BBB penetrability and tissue inflammation. These findings suggest that B1R and B2R have detrimental and beneficial effects, respectively in diabetic cerebral ischaemia, which might open new avenues for the treatment of ischaemic stroke in diabetic patients through selective pharmacological blockade or activation.

Dynamic change of neutrophil to lymphocyte ratio and hemorrhagic transformation after thrombolysis in stroke.

BACKGROUND: The neutrophil to lymphocyte ratio (NLR) has been shown to predict short- and long-term outcomes in ischemic stroke patients. We sought to explore the temporal profile of the plasma NLR in stroke patients treated with intravenous thrombolysis (IVT) and its relationship with intracranial bleeding complications after thrombolysis. METHODS: A total of 189 ischemic stroke patients were prospectively enrolled. Blood samples for leukocyte, neutrophil, and lymphocyte counts were obtained at admission and at 3-6, 12-18, and 36-48 h after IVT. Head CT was performed on admission and repeated after 36-48 h, and a CT scan was done immediately in case of clinical worsening. Hemorrhagic events were categorized as symptomatic intracranial hemorrhage (sICH) and parenchymal hematomas (PH) according to previously published criteria. RESULTS: An increasing trend in the NLR was observed after stroke, and the NLR was higher in patients who developed PH or sICH at 3-6, 12-18, and 36-48 h after IVT (P < 0.01) than in those without PH or sICH. The optimal cutoff value for the serum NLR as an indicator for auxiliary diagnosis of PH and sICH was 10.59 at 12-18 h. Furthermore, the NLR obtained at 12-18-h post-treatment was independently associated with PH (adjusted odds ratio [OR] 1.14) and sICH (adjusted OR 1.14). In addition, patients with a NLR ≥10.59 had an 8.50-fold greater risk for PH (95 % confidence interval [CI] 2.69-26.89) and a 7.93-fold greater risk for sICH (95 % CI 2.25-27.99) than patients with a NLR <10.59. CONCLUSIONS: NLR is a dynamic variable, and its variation is associated with HT after thrombolysis in stroke patients.

Hypertension unawareness among Chinese patients with first-ever stroke.

BACKGROUND: The low rates of hypertension treatment and control, partly due to its unawareness, are the main causes of the high stroke incidence in China. The purpose of this study was to evaluate hypertension unawareness amongst patients with first-ever stroke and to detect factors associated with its unawareness. METHODS: We selected those diagnosed with hypertension from patients with first-ever stroke registered in the Nanjing Stroke Registry Program between 2004 and 2014. These hypertensives were divided as being aware or unaware of their hypertension by using a brief questionnaire conducted shortly after the stroke. Multivariate logistic regression analysis was performed to identify potential factors associated with hypertension unawareness. RESULTS: Of the 5309 patients with first-ever stroke, 3732 (70.3%) were diagnosed with hypertension. Among which, 593 (15.9%) were unaware of their hypertension at the time of stroke onset. Lower-level of education (primary school or illiteracy) and smoking were associated positively with hypertension unawareness; while advanced age, overweight, diabetes mellitus, heart diseases and family history of stroke were associated negatively with hypertension unawareness. Annual data analyzed indicated that the rate of hypertension awareness increased during the past 11 years (r = 0.613, P = 0.045 for trends). CONCLUSIONS: A substantial proportion (15.9%) of Chinese patients with hypertension had not been aware of this covert risk until an overt stroke occurred. Hypertension unawareness was associated with lower educational levels and smoking, which address the importance of health education especially in these individuals.

Human Albumin Improves Long-Term Behavioral Sequelae After Subarachnoid Hemorrhage Through Neurovascular Remodeling.

OBJECTIVE: Subarachnoid hemorrhage results in significant long-lasting neurologic sequelae. Here, we investigated whether human albumin improves long-term outcomes in experimental subarachnoid hemorrhage and whether neurovascular remodeling is involved in the protection of albumin. DESIGN: Laboratory investigation. SETTING: Hospital research laboratory. SUBJECTS: Male Sprague-Dawley rats. INTERVENTIONS: Rats underwent subarachnoid hemorrhage by endovascular perforation. Albumin of either 0.63 or 1.25 g/kg was injected IV immediately after the surgery. Modified Garcia test, beam-walking test, novel object recognition, and Morris water maze were employed to determine the behavioral deficits. The effects of albumin on early neurovascular dysfunction and chronic synaptic plasticity were also studied. MEASUREMENTS AND MAIN RESULTS: Both doses of albumin significantly improved the sensorimotor scores (F = 31.277; p = 0.001) and cognitive performance (F = 7.982; p = 0.001 in novel object recognition test; and F = 3.431; p = 0.026 in the latency analysis of Morris water maze test) for at least 40 days after subarachnoid hemorrhage. There were remarkable microvasculature hypoperfusion, intracranial pressure rise, early vasoconstriction, neural apoptosis, and degeneration in subarachnoid hemorrhage rats, with albumin significantly attenuating such neurovascular dysfunction. Furthermore, albumin markedly prevented blood-brain barrier disruption, as indicated by less blood-brain barrier leakage, preserved blood-brain barrier-related proteins, and dampened gelatinase activities. The expressions of key synaptic elements were up-regulated with albumin supplementation in both acute and chronic phases. Accordingly, a higher dendritic spine density was observed in the prefrontal and hippocampal areas of albumin-treated subarachnoid hemorrhage animals. CONCLUSIONS: Albumin at low-to-moderate doses markedly improves long-term neurobehavioral sequelae after subarachnoid hemorrhage, which may involve an integrated process of neurovascular remodeling.

Reduced endothelial progenitor cells in extracranial arterial stenosis but not intracranial arterial stenosis.

OBJECTIVE: Endothelial progenitor cells (EPCs) are novel markers of endothelial dysfunction and are related to cardiovascular disease. However, their relationship with cerebral atherosclerosis (CA) has not been investigated extensively. We aim to study the relationship between CA severity and EPC subpopulations levels. METHODS: We enrolled 197 patients in this study. EPCs were measured by flow cytometry. Digital subtraction angiography was used to assess CA. Arterial lesion severity was evaluated among cerebral arteries which showed steno-occlusion change and the extent of that condition. RESULTS: There was a significant inverse correlation between EPCs level and CA prevalence after adjusting for confounders (CD45(-/dim)CD34(+)CD309(+) cells: odds ratio [OR], 0.110; 95% confidence interval [CI], 0.026-0.475; P = .00; CD45(-/dim)CD133(+)CD309(+) cells: OR, 0.134; 95% CI, 0.030-0.599; P = .01; CD45(-/dim) CD34(+)CD133(+)CD309(+) cells: OR, 0.010; 95% CI, 0.001-0 .541, P = .02). Multivariate logistic regression analysis showed that only the EPCs level was significantly inversely associated with extracranial atherosclerosis rather than intracranial atherosclerosis (P > .05). CONCLUSIONS: Our data indicated that EPCs subpopulations were independent predictors for CA severity, even after controlling for traditional risk factors.

Validation of NINDS-CSN neuropsychological battery for vascular cognitive impairment in Chinese stroke patients.

BACKGROUND: The NINDS-Canadian Stroke Network (NINDS-CSN) recommended a neuropsychological battery of three protocols to diagnose vascular cognitive impairment (VCI), however, due to culture and language differences, the battery cannot be directly used in China. Validation of the battery in mandarin Chinese is lacking. Our study investigated the reliability and validity of the adapted Chinese versions of the battery in stroke patients with high probability of VCI. METHODS: Fifty mild stroke patients (median of National Institute of Health Stroke Scale [NIHSS] score, 2) and 50 stroke-free normal controls were recruited. All subjects' demographics, clinical history, and stroke severity were recorded. The NINDS-CSN neuropsychological protocols were adapted into the Chinese versions. External validity, defined as the ability of the protocol summary scores to differentiate stroke patients from controls, was determined using the area under the curve (AUC) of the receiver operating characteristics curve. We also evaluated internal consistency and intra-rater reliability. RESULTS: Stroke patients performed significantly poorer than controls on all three protocols (F statistics between 24.9 and 31.4, P < 0.001). External validity evaluated by AUCs was 0.88 (95% confidence interval [CI], 0.81-0.95), 0.88 (95% CI, 0.81-0.94), and 0.86 (95% CI, 0.79-0.94) for the 60-min, 30-min and 5-min protocols, respectively. Cronbach's alpha of the cognitive tests was 0.87 for all subjects. Intra-rater reliability was acceptable with intraclass correlation coefficients 0.90, 0.83 and 0.75 for the 60-min, 30-min and 5-min protocols, respectively. CONCLUSIONS: The adapted Chinese versions of three NINDS-CSN neuropsychological protocols were valid and reliable for assessing VCI in Chinese patients with mild stroke.

GSK3ß is a checkpoint for TNF-α-mediated impaired osteogenic differentiation of mesenchymal stem cells in inflammatory microenvironments.

BACKGROUND: The fate and differentiation of mesenchymal stem cells (MSCs) depend on various microenvironmental cues. In chronic inflammatory bone disease, bone regeneration is inhibited. The present study therefore sought to identify the underlying molecule mechanisms. METHODS: We isolated periodontal ligament stem cells (PDLSCs), a new population of MSCs, from the periodontal ligament tissues of periodontitis patients and healthy controls (p-PDLSCs and h-PDLSCs). The secretion of inflammatory cytokines, like TNF-α, IL-1ß, IL-6 and IL-8, after LPS stimulation was measured by ELISA. The expressions of p-GSK3ß and GSK3ß in two types of PDLSCs were detected by Western blot. TOPFlash was used to assay the Tcf/Lef transcriptional activity. Knockdown of GSK3ß by siRNA and over-expression of GSK3ß by adenoviruses were performed to confirm the role of GSK3ß in the impaired osteogenic differentiation of PDLSCs under inflammatory microenvironment. RESULTS: We demonstrated that p-PDLSCs displayed impaired osteogenic capacity than h-PDLSCs. Upon inflammatory stimulation, monocytes, but not PDLSCs, released inflammatory cytokines among which TNF-α directly act on PDLSCs and suppressed their osteogenic differentiation. TNF-α induced the phosphorylation of GSK3ß, the deactivated form of GSK3ß, which increased nuclear ß-catenin and Lef-1 accumulation, and eventually reduced the Runx2-associated osteogenesis in PDLSCs. Over-expression of GSK3ß rescued osteogenesis in TNF-α-stimulated PDLSCs, whereas inactivation of GSK3ß was sufficient to liberate the ß-catenin/Lef-1/Runx2 pathway. CONCLUSION: GSK3ß plays an obligatory role in the TNF-α-mediated inhibition of osteogenesis in MSCs. GENERAL SIGNIFICANCE: The strategy to target GSK3ß may provide a potential approach to bone regeneration in inflammatory microenvironments.

Ginsenoside Rd attenuates tau protein phosphorylation via the PI3K/AKT/GSK-3ß pathway after transient forebrain ischemia.

Phosphorylated tau was found to be regulated after cerebral ischemia and linked to high risk for the development of post-stroke dementia. Our previous study showed that ginsenoside Rd (Rd), one of the main active ingredients in Panax ginseng, decreased tau phosphorylation in Alzheimer model. As an extending study, here we investigated whether Rd could reduce tau phosphorylation and sequential cognition impairment after ischemic stroke. Sprague-Dawley rats were subjected to focal cerebral ischemia. The tau phosphorylation of rat brains were analyzed following ischemia by Western blot and animal cognitive functions were examined by Morris water maze and Novel object recognition task. Ischemic insults increased the levels of phosphorylated tau protein at Ser199/202 and PHF-1 sites and caused animal memory deficits. Rd treatment attenuated ischemia-induced enhancement of tau phosphorylation and ameliorated behavior impairment. Furthermore, we revealed that Rd inhibited the activity of Glycogen synthase kinase-3ß (GSK-3ß), the most important kinase involving tau phosphorylation, but enhanced the activity of protein kinase B (PKB/AKT), a key kinase suppressing GSK-3ß activity. Moreover, we found that LY294002, an antagonist for phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, abolished the inhibitory effect of Rd on GSK-3ß activity and tau phosphorylation. Taken together, our findings provide the first evidence that Rd may reduce cerebral ischemia-induced tau phosphorylation via the PI3K/AKT/GSK-3ß pathway.

Trajectories of stroke severity and functional outcomes after endovascular treatment in ischemic stroke: A post hoc analysis of a randomized controlled trial.

BACKGROUND: The trajectory of early neurological changes in patients with acute ischemic stroke has been understudied. This study aimed to investigate the association between longitudinal trajectories of stroke severity and 90-day functional outcomes in patients with acute ischemic stroke receiving endovascular treatment. METHODS: We enrolled patients from a prospective, multicenter, randomized controlled trial. The stroke severity was assessed with the National Institute of Health Stroke Scale at the pre-procedure, 24 hours, and seven days after the procedure. Group-based trajectory modeling (GBTM) was used to identify trajectories of stroke severity. Multivariable logistic regression was performed to explore the association between stroke severity markers and 90-day functional outcomes. RESULTS: Of 218 enrolled patients, 127 (58.3%) had poor functional outcomes at 90 days. We identified three trajectories of stroke severity in the GBTM: stable symptom (38.1%), symptom deterioration (17.0%), and symptom improvement (44.9%). In multivariable analyses, trajectories of stroke severity were associated with an increased risk of poor functional outcomes (symptom improvement versus symptom deterioration: odds ratio, 0.007; 95% confidence interval, 0.001-0.040; P <0.001). Reclassification indexes revealed that trajectories of stroke severity would increase the predictive ability for poor functional outcomes at 90 days. CONCLUSION: After endovascular treatment, patients would follow one of three distinct trajectories of stroke severity. Symptom deterioration trajectory was associated with an increased risk of poor functional outcomes at 90 days. TRIAL REGISTRATION NUMBER: NCT04973332.

Periprocedural intravenous heparin in patients with acute ischemic stroke treated with endovascular thrombectomy after intravenous thrombolysis.

OBJECTIVE: The benefit-to-risk ratio of periprocedural heparin in patients treated with endovascular thrombectomy (EVT) after intravenous thrombolysis (IVT) remains unclear. This study aimed to evaluate the potential effects of periprocedural heparin on clinical outcomes of EVT after IVT. METHODS: The authors retrospectively analyzed patients from multicenter studies treated with EVT after IVT in the anterior circulation. The endpoints were unfavorable outcome (defined as modified Rankin Scale score ≥ 3 at 90 days), 90-day mortality, symptomatic intracranial hemorrhage (SICH), successful recanalization, and early neurological deterioration. Patients were divided into two groups based on whether they were treated with heparin (heparin-treated group) or not (untreated group), and the efficacy and safety outcomes were compared using multivariable logistic regression models and propensity score-matching methods. RESULTS: Among the 322 included patients (mean age 67.4 years, 54.3% male), 32% of patients received periprocedural heparin. In multivariable analyses, the administration of periprocedural heparin was a significant predictor for unfavorable outcome (OR 2.821, 95% CI 1.15-7.326; p = 0.027), SICH (OR 24.925, 95% CI 2.363-780.262; p = 0.025), and early neurological deterioration (OR 5.344, 95% CI 1.299-28.040; p = 0.029). Regarding successful recanalization and death, no significant differences between the groups were found after propensity score matching. CONCLUSIONS: The results showed that periprocedural heparin is associated with an increased risk of unfavorable outcomes and SICH in patients treated with EVT after IVT. Further studies are warranted to evaluate the utility and safety of periprocedural heparin.

Angiography­based quantitative flow ratio for functional assessment of intracranial atherosclerotic disease.

BACKGROUND: Intracranial atherosclerotic stenosis (ICAS), an important cause of stroke, is associated with a considerable stroke recurrence rate despite optimal medical treatment. Further assessment of the functional significance of ICAS is urgently needed to enable individualised treatment and, thus, improve patient outcomes. AIMS: We aimed to evaluate the haemodynamic significance of ICAS using the quantitative flow ratio (QFR) technique and to develop a risk stratification model for ICAS patients. METHODS: Patients with moderate to severe stenosis of the middle cerebral artery, as shown on angiography, were retrospectively enrolled. For haemodynamic assessment, the Murray law-based QFR (µQFR) was performed on eligible patients. Multivariate logistic regression models composed of µQFR and other risk factors were developed and compared for the identification of symptomatic lesions. Based on the superior model, a nomogram was established and validated by calibration. RESULTS: Among 412 eligible patients, symptomatic lesions were found in 313 (76.0%) patients. The µQFR outperformed the degree of stenosis in discriminating culprit lesions (area under the curve [AUC]: 0.726 vs 0.631; DeLong test p-value=0.001), and the model incorporating µQFR and conventional risk factors also performed better than that containing conventional risk factors only (AUC: 0.850 vs 0.827; DeLong test p-value=0.034; continuous net reclassification index=0.620, integrated discrimination improvement=0.057; both p<0.001). The final nomogram showed good calibration (p for Hosmer-Lemeshow test=0.102) and discrimination (C-statistic 0.850, 95% confidence interval: 0.812-0.883). CONCLUSIONS: The µQFR was significantly associated with symptomatic ICAS and outperformed the angiographic stenosis severity. The final nomogram effectively discriminated symptomatic lesions and may provide a useful tool for risk stratification in ICAS patients.

Sevoflurane preconditioning improves mitochondrial function and long-term neurologic sequelae after transient cerebral ischemia: role of mitochondrial permeability transition.

OBJECTIVE: Anesthetic preconditioning appears to be a viable strategy to treat ischemic cerebral injury. Here we investigated 1) whether the protection conferred by sevoflurane preconditioning sustains in time; 2) whether sevoflurane preconditioning diminishes mitochondrial dysfunction following cerebral ischemia; and 3) whether mitochondrial permeability transition pore plays a crucial role in the sevoflurane preconditioning. DESIGN: Laboratory investigation. SETTING: University research laboratory. SUBJECTS: : Sprague-Dawley rats. INTERVENTIONS: Rats underwent 2 hrs of focal cerebral ischemia induced by middle cerebral artery occlusion. Preconditioning was elicited with sevoflurane (2.3%) for 60 mins at 24 hrs before ischemia. The involvement of mitochondrial permeability transition pore was determined with a mitochondrial permeability transition pore opener atractyloside and a specific mitochondrial permeability transition pore inhibitor cyclosporin A. In vitro study was performed on acutely isolated mitochondria subjected to calcium overload. MEASUREMENTS AND MAIN RESULTS: Sevoflurane preconditioning significantly decreased the infarct size by 35.9% (95% confidence interval 6.5-28.4, p < .001). This reduction of injury volume was associated with a long-term improvement of neurological function according to modified neurological severity score (F = 13.6, p = .001) and sticky-tape test (F = 29.1, p < .001) for 42 days after ischemia. Furthermore, sevoflurane preconditioning markedly protected mitochondria, as indicated by preserved respiratory chain complex activities and membrane potential, lowered mitochondrial hydrogen-peroxide production, and attenuated mitochondrial permeability transition pore opening. Isolated mitochondria also demonstrated a reduced sensitivity to Ca-induced mitochondrial permeability transition pore opening after pre-exposure to sevoflurane in vitro (95% confidence interval 24.2-196.5,p = .006). Inhibiting mitochondrial permeability transition pore using cyclosporin A resulted in protective effects similar to those seen with sevoflurane preconditioning, whereas pharmacologically opening the mitochondrial permeability transition pore with atractyloside abrogated all the positive effects of sevoflurane preconditioning and cyclosporin A, including suppression of mitochondrial permeability transition pore opening, counteraction of mitochondria-dependent apoptotic pathway, and subsequent histological and behavioral improvements. CONCLUSIONS: Sevoflurane preconditioning protects mitochondria from cerebral ischemia/reperfusion injury and ameliorates long-term neurological deficits. Inhibition of mitochondrial permeability transition pore opening is a crucial step in mediating the neuroprotection of sevoflurane preconditioning.

Ginsenoside Rd protects neurons against glutamate-induced excitotoxicity by inhibiting ca(2+) influx.

Our previous studies have demonstrated that ginsenoside Rd (GSRd), one of the principal ingredients of Pana notoginseng, has neuroprotective effects against ischemic stroke. However, the possible mechanism(s) underlying the neuroprotection of GSRd is/are still largely unknown. In this study, we treated glutamate-injured cultured rat hippocampal neurons with different concentrations of GSRd, and then examined the changes in neuronal apoptosis and intracellular free Ca(2+) concentration. Our MTT assay showed that GSRd significantly increased the survival of neurons injured by glutamate in a dose-dependent manner. Consistently, TUNEL and Caspase-3 staining showed that GSRd attenuated glutamate-induced cell death. Furthermore, calcium imaging assay revealed that GSRd significantly attenuated the glutamate-induced increase of intracellular free Ca(2+) and also inhibited NMDA-triggered Ca(2+) influx. Thus, the present study demonstrates that GSRd protects the cultured hippocampal neurons against glutamate-induced excitotoxicity, and that this neuroprotective effect may result from the inhibitory effects of GSRd on Ca(2+) influx.