Advances in Stroke 2017

Development and Validation of the Short-LIMOS for the Acute Stroke Unit-A Short Version of the Lucerne ICF-Based Multidisciplinary Observation Scale

Introduction

At hospital stroke units, the time available to assess the patient's limitations in activities and participation is limited, although being essential for discharge planning. Till date, there is no quick-to-perform instrument available that captures the patient's actual performance during daily activities from a motor, cognitive, and communication perspective within the International Classification of Functioning, Disability and Health (ICF) framework. Therefore, the aim was to develop and validate a shortened version of the Lucerne ICF-Based Multidisciplinary Observation Scale (Short-LIMOS) that observes the patient's performance across ICF-domains and is applicable in the context of an acute stroke unit.

Methods

The Short-LIMOS was developed by reducing the original 45-item LIMOS to the ten most important items using a multivariable linear regression ANOVA with data of 836 stroke patients collected during inpatient neurorehabilitation. The Short-LIMOS's reliability, validity, and responsiveness were evaluated with data of 416 stroke patients in the acute stroke unit.

Results

A significant equation [F _(10,825) = 232.083] with R ² of 0.738 was found for the following ten items for the Short-LIMOS: maintaining a body position (d415), changing basic body position (d410), climbing stairs (d4551), eating (d550), dressing (d540), communicating with-receiving-written messages (reading) (d325), applying knowledge, remembering facts (d179), solving complex problems (d1751), making simple decisions (d177), and undertaking a simple task (d2100). Principal component analysis revealed a Short-LIMOS motor and a Short-LIMOS cognition/communication component. The Short-LIMOS had a high internal consistency and good test-retest reliability. A moderate construct validity was shown by the significant correlation with the Barthel Index. The Short-LIMOS had neither floor nor ceiling effects.

Discussion and Conclusion

The developed Short-LIMOS was found to be reliable and valid within a population of (hyper)acute and subacute stroke patients. The added value of this multidisciplinary assessment is its comprehensiveness by capturing the patient's actual performance on the motor, cognitive, and communication domain embedded in an ICF-framework in <10 mins.

Stroke and Etiopathogenesis: What Is Known?

Background: A substantial portion of stroke risk remains unexplained, and a contribution from genetic factors is supported by recent findings. In most cases, genetic risk factors contribute to stroke risk as part of a multifactorial predisposition. A major challenge in identifying the genetic determinants of stroke is fully understanding the complexity of the phenotype. Aims: Our narrative review is needed to improve our understanding of the biological pathways underlying the disease and, through this understanding, to accelerate the identification of new drug targets. Methods: We report, the research in the literature until February 2022 in this narrative review. The keywords are stroke, causes, etiopathogenesis, genetic, epigenetic, ischemic stroke. Results: While better risk prediction also remains a long-term goal, its implementation is still complex given the small effect-size of genetic risk variants. Some authors encourage the use of stroke genetic panels for stroke risk assessment and further stroke research. In addition, new biomarkers for the genetic causes of stroke and new targets for gene therapy are on the horizon. Conclusion: We summarize the latest evidence and perspectives of ischemic stroke genetics that may be of interest to the physician and useful for day-to-day clinical work in terms of both prevention and treatment of ischemic stroke.

Ischemic Stroke Genetics: What Is New and How to Apply It in Clinical Practice?

The etiology of ischemic stroke is multifactorial. Although receiving less emphasis, genetic causes make a significant contribution to ischemic stroke genesis, especially in early-onset stroke. Several stroke classification systems based on genetic information corresponding to various stroke phenotypes were proposed. Twin and family history studies, as well as candidate gene approach, are common methods to discover genetic causes of stroke, however, both have their own limitations. Genome-wide association studies and next generation sequencing are more efficient, promising and increasingly used for daily diagnostics. Some monogenic disorders, despite covering only about 7% of stroke etiology, may cause well-known clinical manifestations that include stroke. Polygenic disorders are more frequent, causing about 38% of all ischemic strokes, and their identification is a rapidly developing field of modern stroke genetics. Current advances in human genetics provide opportunity for personalized prevention of stroke and novel treatment possibilities. Genetic risk scores (GRS) and extended polygenic risk scores (PRS) estimate cumulative contribution of known genetic factors to a specific outcome of stroke. Combining those scores with clinical information and risk factor profiles might result in better primary stroke prevention. Some authors encourage the use of stroke gene panels for stroke risk evaluation and further stroke research. Moreover, new biomarkers for stroke genetic causes and novel targets for gene therapy are on the horizon. In this article, we summarize the latest evidence and perspectives of ischemic stroke genetics that could be of interest to the practitioner and useful for day-to-day clinical work.

Anti-Stroke Chinese Herbal Medicines Inhibit Abnormal Amyloid-β Protein Precursor Processing in Alzheimer's Disease

BACKGROUND

Chinese Herbal Medicines (CHMs), as an important and integral part of a larger system of medicine practiced in China, called Traditional Chinese Medicine (TCM), have been used in stroke therapy for centuries. A large body of studies suggest that some Chinese herbs can help reverse cognitive impairment in stroke patients, while whether these herbs also exert therapeutic benefits for Alzheimer's disease remains to be seen.

OBJECTIVE

To address this issue, we selected four types of CHMs that are commonly prescribed for stroke treatment in clinical practice, namely DengZhanXiXin (D1), TongLuoJiuNao (T2), QingKaiLing (Q3), and HuangQinGan (H4), and tested their effects on amyloid-β protein precursor (AβPP) processing in vitro.

METHODS

AβPP, β-secretase (BACE1), and 99-amino acid C-terminal fragment of AβPP (C99) stably transfected cells were used for the tests of AβPP processing. The production of Aβ, activity of BACE1, neprilysin (NEP), and γ-secretase were assessed by ELISA, RT-PCR, and western blot.

RESULTS

By upregulating BACE1 activity, D1 increased Aβ production whereas decreased the ratio of Aβ 42/Aβ 40; by downregulating BACE1 activity and modulating the expression of γ-secretase, T2 decreased Aβ production and the ratio of Aβ 42/Aβ 40; by downregulating BACE1 activity, Q3 decreased Aβ production; H4 did not change Aβ production due to the simultaneously downregulation of BACE1 and NEP activity.

CONCLUSION

Our study indicates that these four anti-stroke CHMs regulate AβPP processing through different mechanisms. Particularly, T2 with relatively simple components and prominent effect on AβPP processing may be a promising candidate for the treatment of AD.

Super-assembled silica nanoprobes for intracellular Zn(II) sensing and reperfusion injury treatment through in situ MOF crystallization

The production of excess free zinc ions (Zn²⁺) in cells has been identified as an important cause of cell injury or apoptosis after ischemia reperfusion. Thus, developing a nanosystem with multiple therapeutic functions to significantly eliminate multiple cell injury factors is of great interest. Here, a super-assembled nanosystem consisting of a polyethylene glycol (PEG) surface-modified mesoporous silica nanoparticle (MSN) encapsulating 2-methylimidazole (2MI) and a Zn²⁺ probe (PZn) was fabricated. The 2MI-P@MSN nanoassemblies showed a "turn-on" fluorescence signal at 476 nm toward zinc ions due to the presence of PZn. Besides, zeolitic imidazolate framework-8 (ZIF-8) could be assembled on the site intracellularly after 2MI chelating with free zinc ions. The experimental results revealed that 2MI-P@MSN exhibited excellent biocompatibility and non-cytotoxicity, and was able to provide satisfactory protection to OGD/R-treated cells based on zinc ion adsorption and the antioxidant effect of ZIF-8, which could effectively improve the survival rate of reperfusion injury cells from 52% to 73%. Notably, selective and quantitative sensing of Zn²⁺ was successfully carried out in the cells. This strategy highlights the potential of the detection, absorption and assembly of excess zinc ions simultaneously for cell therapy, which provides a promising therapeutic method for ischemic stroke, oxidative damage and diseases associated with zinc ion accumulation.

CircDLGAP4 overexpression relieves oxygen-glucose deprivation-induced neuronal injury by elevating NEGR1 through sponging miR-503-3p

Circular RNAs (circRNAs) have been reported to play vital regulatory roles in human diseases. However, the functions of circRNAs in ischemic stroke (IS) are limited. In this study, we aimed to explore the functions and mechanisms of circRNA DLG associated protein 4 (circDLGAP4) in IS development. Oxygen-glucose deprivation (OGD)-treated HCN-2 cells were used to mimic IS environment in vitro. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was used to detect the levels of circDLGAP4, microRNA-503-3p (miR-503-3p) and neuronal growth regulator 1 (NEGR1) mRNA. RNase R assay was conducted to analyze the stability of circDLGAP4. Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis were adopted for cell viability and death, respectively. Western blot assay was performed for protein levels. Enzyme-linked immunosorbent assay (ELISA) kits were used to examine the concentrations of inflammatory cytokines. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA pull-down assay were employed to analyze the relationships among circDLGAP4, miR-503-3p and NEGR1. CircDLGAP4 level was declined in HCN-2 cells after OGD treatment. CircDLGAP4 overexpression promoted cell viability and suppressed cell death and inflammatory cytokine concentrations in OGD-treated HCN-2 cells. CircDLGAP4 acted as the sponge for miR-503-3p and the impacts of circDLGAP4 overexpression on cell viability, death and inflammation in OGD-treated HCN-2 cells were reversed by miR-503-3p elevation. Furthermore, NEGR1 was the target gene of miR-503-3p. MiR-503-3p inhibition ameliorated OGD-induced HCN-2 cell impairments, but NEGR1 knockdown abolished the effects. CircDLGAP4 alleviated OGD-induced HCN-2 cell damage by regulating miR-503-3p/NEGR1 axis.

Association of Proinflammatory Cytokine Levels with Stroke Severity, Infarct Size, and Muscle Strength in the Acute Phase of Stroke

OBJECTIVE

Patterns of cytokine levels and their association with stroke severity, infarct size, and muscle strength are obscure. We aimed to analyze the immune mediators linked to T helper (Th)1, Th2, Th17, and regulatory T cell patterns and their association with stroke severity, infarct size, and muscle strength.

MATERIALS AND METHODS

We included patients with acute stroke (n = 15) and healthy non-disabled individuals (n = 20) aged > 18 years. The dependent variables were stroke severity according to the National Institute of Health Stroke Scale (NIHSS), infarct size on computed tomography, handgrip strength by dynamometry, and global muscle strength according to the Medical Research Council (MRC) scale. The independent variables were the circulating cytokine levels. The cytokine levels were compared between the groups, and correlations between the clinical data were verified.

RESULTS

The stroke group had higher interleukin (IL)-6 (p < 0.0001) and IL-10 (p < 0.0001) levels, but lower tumor necrosis factor (TNF)-α (p = 0.036) levels than the control group. IL-10 and soluble tumor necrosis factor receptor (sTNF-RII) levels were correlated with each other (r = 0.533; p = 0.042) and infarct size (r = 0.653; p = 0.033 and r = 0.689; p = 0.018, respectively). MRC scores were positively and negatively correlated with handgrip strength of the affected side (r = 0.78; p = 0.001) and NIHSS scores (r = -0.87; p < 0.0001), respectively.

CONCLUSIONS

Plasma levels of some cytokines were associated with changes in the acute phase of stroke, and IL-10 and sTNF-RII levels are potential biomarkers of infarct size.

What do stroke survivors' value about participating in research and what are the most important research problems related to stroke or transient ischemic attack (TIA)? A survey

Background

Recruitment to stroke clinical trials is challenging, but consumer registers can facilitate participation. Researchers need to understand the key factors that facilitate trial involvement and improve consumer partnerships to identify what research topics important to stroke and transient ischemic attack (TIA) survivors and their carers. We aimed to examine i) the experience of being involved in a stroke research register, and ii) the priorities for stroke research from the perspective of stroke survivors.

Methods

Online and paper-based surveys were sent directly to members of a stroke register and disseminated online. Multiple choice questions were reported as counts and percentages and open-ended questions were thematically analysed using Braun and Clarke’s 6-stage process.

Results

Of 445 survey respondents, 154 (38%) were a member of the Stroke Research Register. The most frequently reported reason for research participation was to help others in the future. Respondents reported they were less likely to take part in research if the research question was not relevant to them, if transport was an issue, or because they lacked time. The most important research problems reported were targeting specific impairments including recovery of movement, fatigue, and aphasia, improvement of mental health services, and increased support for carers.

Conclusions

Recruitment to trials may be improved by research registers if an inclusive research culture is fostered, in which consumers feel valued as members of a community, have direct and timely access to research findings and the opportunity to be meaningfully involved in research around the problems that consumers find most important.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01390-y.

Knockdown of lncRNA SNHG15 Ameliorates Oxygen and Glucose Deprivation (OGD)-Induced Neuronal Injury via Regulating the miR-9-5p/TIPARP Axis

Stroke is a cerebrovascular disease with impaired nerve function. Long non-coding RNA (lncRNA) is considered to be an important regulator of various diseases. Nevertheless, the role of lncRNA small nucleolar RNA host gene 15 (SNHG15) in cerebral ischemia injury induced by stroke is still unclear. Cell-counting kit 8 assay and flow cytometry were used to detect cell viability and apoptosis, respectively. The caspase3 activity of cells was measured using Caspase3 Activity Assay Kit. Besides, the protein levels of apoptosis markers and TCCD-induced poly (ADP)-ribose polymerase (TIPARP) were determined using western blot analysis. Moreover, quantitative real-time polymerase chain reaction was employed to examine the relative expression of SNHG15 and miR-9-5p. Furthermore, dual-luciferase reporter assay was used to assess the interaction between miR-9-5p and SNHG15 or TIPARP. In addition, biotin-labeled RNA pull-down assay was performed to evaluate the interaction between miR-9-5p and SNHG15 further. Middle cerebral artery occlusion (MCAO) model was constructed to further explore the role of SNHG15 in neuronal injury in vivo. Our data showed that oxygen and glucose deprivation (OGD) could induce N-2a cell injury and enhance SNHG15 expression. Silenced SNHG15 could promote the viability and suppress the apoptosis of OGD-induced N-2a cells. Also, SNHG15 knockdown also could alleviate the neuronal injury of MCAO mice. Mechanistically, SNHG15 could sponge miR-9-5p, and miR-9-5p could target TIPARP. Further experiments revealed that miR-9-5p inhibition or TIPARP overexpression could reverse the suppressive effect of SNHG15 knockdown on OGD-induced N-2a cell injury. Our findings indicated that SNHG15 knockdown inhibited neuronal injury through the miR-9-5p/TIPARP axis, suggesting that SNHG15 might be a potential target for cerebral ischemia injury induced by stroke.

Study of common quantification methods of amide proton transfer magnetic resonance imaging for ischemic stroke detection

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.

Are patient educational resources effective at deterring stroke survivors from considering experimental stem cell treatments? A randomized controlled trial

OBJECTIVE

To evaluate whether online resources developed to educate people about the risks associated with experimental stem cell (SC) treatments influence stroke survivors' attitudes about the safety and effectiveness of these treatments.

METHODS

Adult stroke survivors who had not previously received SC treatments (N = 112) were recruited from international stroke advocacy/support groups for a prospective, parallel-group randomized controlled trial. Participants indicated whether they were considering SC treatments (yes/no) prior to, immediately following, and 30-days after reading/viewing the International Society for Stem Cell Research booklet or Stem Cell Network video. Participant attitudes regarding the safety, effectiveness, accessibility and affordability of SC treatments were examined on each occasion, and compared to those of a waitlist control group.

RESULTS

Significantly fewer participants were considering SC treatments immediately after reading the SC research booklet (p =.031), although neither intervention had any impact after 30-days (p >.05). Waitlist and intervention groups reported positive attitudes toward SC treatments at each assessment.

CONCLUSIONS

Stroke survivor attitudes toward SC treatments were initially influenced by the patient booklet, however these changes were not maintained.

PRACTICAL IMPLICATIONS

Clinicians are encouraged to initiate discussions about experimental SC treatments during inpatient rehabilitation and to reinforce the risks throughout subsequent care.

Ginkgol Biloba extract as an adjunctive treatment for ischemic stroke: A systematic review and meta-analysis of randomized clinical trials

OBJECTIVE

Ginkgo biloba extract (GBE) is widely used as an adjunctive treatment for ischemic stroke. This meta-analysis aimed to evaluate the effectiveness and safety of GBE specifically for long-term users at the convalescence stage of ischemic stroke.

METHODS

MEDLINE, Cochrane Central Register of Controlled Trials, Embase Database, WHO Clinical Trials Registration Platform, Chinese National Knowledge Infrastructure, Wanfang Database, and Chinese Scientific Journal Database were searched from inception to 20 September 2018. Risk ratio (RR) and mean difference (MD) with a 95% confidence interval (CI) were used as effect estimates using RevMan software (5.3; Review Manager [RevMan], Nordic Cochrane Centre, Copenhagen, Denmark). A meta-analysis was performed where data were available. A trial sequential analysis was used to control random errors for recurrence rate and the GRADE (grading of recommendations, assessment, development, and evaluations) approach was used to assess the quality of the body of evidence. The meta-analysis design was registered on PROSPERO (CRD42018110211, http://www.crd.york.ac.uk/PROSPERO).

RESULTS

We identified 15 randomized clinical trials involving 1829 participants. The majority of the included trials were of high risk of bias in methodological quality. For acute ischemic stroke, adding GBE to conventional therapy led to higher Barthel index scores (MD: 5.72; 95% CI: 3.11-8.33) and lower neurological function deficit scores (MD: -1.39; 95% CI: -2.15 to -0.62). For patients in their convalescence (or sequelae) stage of ischemic stroke, GBE was superior in improving dependence (MD: 7.17; 95% CI: 5.96-8.38) and neurological function deficit scores (MD: -1.15; 95% CI: -1.76 to -0.53) compared with placebo or conventional therapy, but there was no difference in vascular events (RR: 0.70; 95% CI: 0.44-1.14), recurrence rate (RR: 0.57; 95% CI: 0.26-1.25; trial sequential analysis: conclusive) and mortality (RR: 1.07; 95% CI: 0.41-2.81).

CONCLUSIONS

GBE appears to improve neurological function and dependence compared with conventional therapy for ischemic stroke at different stages and appears generally safe for clinical application. The lack of improvement in recurrence rate was confirmed by trial sequential analysis. Due to the generally weak evidence, further large, rigorous trials are warranted.

Value-based healthcare in ischemic stroke care: case-mix adjustment models for clinical and patient-reported outcomes

Background

Patient-Reported Outcome Measures (PROMs) have been proposed for benchmarking health care quality across hospitals, which requires extensive case-mix adjustment. The current study’s aim was to develop and compare case-mix models for mortality, a functional outcome, and a patient-reported outcome measure (PROM) in ischemic stroke care.

Methods

Data from ischemic stroke patients, admitted to four stroke centers in the Netherlands between 2014 and 2016 with available outcome information (N = 1022), was analyzed. Case-mix adjustment models were developed for mortality, modified Rankin Scale (mRS) scores and EQ-5D index scores with respectively binary logistic, proportional odds and linear regression models with stepwise backward selection. Predictive ability of these models was determined with R-squared (R²) and area-under-the-receiver-operating-characteristic-curve (AUC) statistics.

Results

Age, NIHSS score on admission, and heart failure were the only common predictors across all three case-mix adjustment models. Specific predictors for the EQ-5D index score were sex (β = 0.041), socio-economic status (β = − 0.019) and nationality (β = − 0.074). R²-values for the regression models for mortality (5 predictors), mRS score (9 predictors) and EQ-5D utility score (12 predictors), were respectively R² = 0.44, R² = 0.42 and R² = 0.37.

Conclusions

The set of case-mix adjustment variables for the EQ-5D at three months differed considerably from the set for clinical outcomes in stroke care. The case-mix adjustment variables that were specific to this PROM were sex, socio-economic status and nationality. These variables should be considered in future attempts to risk-adjust for PROMs during benchmarking of hospitals.

Models of poststroke depression and assessments of core depressive symptoms in rodents: How to choose?

Our previous studies have indicated that depression and declined cognition have been involved in some neurodegenerative diseases including Stroke, Parkinson's diseases and Vascular Parkinsonism. Post-stroke depression (PSD) is the most common psychiatric disorder following a stroke and has high morbidity and mortality. Studies on PSD are increasingly common, but the specific mechanisms remain unknown. Current research mainly includes clinical and animal aspects. Questionnaires and peripheral blood examination are two of the most common methods used to study clinical PSD. The results of questionnaires are influenced by multiple factors such as disease history, education background, occupation, economic status, family relationships and social support. There are certain limitations to blood sample testing; for example, it is influenced by cerebrovascular diseases and some other disruptions of the internal environment. It is difficult for either method to fully clarify the pathophysiological mechanism of PSD. Animal models provide alternative methods to further understand the pathophysiological mechanisms of PSD, such as the involvement of neuronal circuits and cytokines. More than ten animal models of PSD have been developed, and new models are constantly being introduced. Therefore, it is important to choose the appropriate model for any given study. In this paper, we will discuss the characteristics of the different models of PSD and comment on the advantages and disadvantages of each model, drawing from research on model innovation. Finally, we briefly describe the current assessment methods for the core symptoms of PSD models, point out the shortcomings, and present the improved sucrose preference test as a rational evaluation of anhedonia.

Mind-Body Interventions, Psychological Stressors, and Quality of Life in Stroke Survivors

Background and Purpose- Psychological stressors, including poststroke depression, poststroke anxiety, and posttraumatic stress disorder, are highly prevalent in stroke survivors. These symptoms exact a significant toll on stroke survivors. Clinical and research efforts in stroke recovery focus on motor disability, speech and language deficits, and cognitive dysfunction while largely neglecting psychological stressors. Evidence suggests mind-body interventions in other chronic illness populations decrease symptoms of depression, regulate immune responses, and promote resilience, yet similar studies are lacking in stroke populations. This review aims to synthesize evidence of the effects of mind-body interventions on psychological stressors, quality of life, and biological outcomes for stroke survivors. Methods- A systematic search of PubMed, PsycINFO, and CINAHL was conducted from database inception to November 2017. Results- Eight studies were included in the review, with a total of 292 participants. Mind-body interventions included yoga or tai chi. Of the 5 included randomized controlled trials, most were pilot or feasibility studies with small sample sizes. Psychological stressors, including poststroke depression and anxiety, along with the quality of life, improved over time, but statistically significant between-group differences were largely absent. The 3 included studies with a qualitative design reported themes reflecting improvement in psychological stressors and quality of life. No included studies reported biological outcomes. Conclusions- Studies of mind-body interventions suggest a possible benefit on psychological stressors and quality of life; however, rigorously designed, sufficiently powered randomized controlled trials with mixed-methods design are warranted to delineate specific treatment effects of these interventions. Studies with both biological and psychological stressors as outcomes would provide evidence about interaction effects of these factors on stroke-survivor responses to mind-body interventions.

Matrix metalloproteinases and ADAMs in stroke

Stroke is a leading cause of death and disability worldwide. However, after years of in-depth research, the pathophysiology of stroke is still not fully understood. Increasing evidence shows that matrix metalloproteinases (MMPs) and "a disintegrin and metalloproteinase" (ADAMs) participate in the neuro-inflammatory cascade that is triggered during stroke but also in recovery phases of the disease. This review covers the involvement of these proteins in brain injury following cerebral ischemia which has been widely studied in recent years, with efforts to modulate this group of proteins in neuroprotective therapies, together with their implication in neurorepair mechanisms. Moreover, the review also discusses the role of these proteins in specific forms of neurovascular disease, such as small vessel diseases and intracerebral hemorrhage. Finally, the potential use of MMPs and ADAMs as guiding biomarkers of brain injury and repair for decision-making in cases of stroke is also discussed.

Efficacy and Mechanism of Panax Ginseng in Experimental Stroke

Stroke is one of the leading causes of death and long-term disability worldwide. However, effective therapeutic approaches are still limited. The disruption of blood supply triggers complicated temporal and spatial events involving hemodynamic, biochemical, and neurophysiologic changes, eventually leading to pathological disturbance and diverse clinical symptoms. Ginseng (Panax ginseng), a popular herb distributed in East Asia, has been extensively used as medicinal and nutritional supplements for a variety of disorders worldwide. In recent years, ginseng has displayed attractive beneficial effects in distinct neurological disorders including stroke, involving multiple protective mechanisms. In this article, we reviewed the literature on ginseng studies in the experimental stroke field, particularly focusing on the in vivo evidence on the preventive or therapeutic efficacy and mechanisms of ginseng and ginsenosides in various stroke models of mice and rats. We also summarized the efficacy and underlying mechanisms of ginseng and ginsenosides on short- and long-term stroke outcomes.

Vitexin protects against ischemia/reperfusion-induced brain endothelial permeability

Brain endothelial permeability plays a crucial role in blood-brain barrier (BBB), but the permeability enhancement in cerebral ischemia reperfusion (I/R). Vitexin has certain neuroprotective effects, but the effect brain endothelial permeability in I/R injury was unknown. In this study, the effects of Vitexin on endothelial permeability and the underlying mechanisms in human brain microvascular endothelial cells (HBMEc) I/R injury model were investigated. Cell viability, lactate dehydrogenase (LDH), inflammation and apoptosis were detected. The effects of Vitexin on BBB integrity tight junction, matrix metalloproteinases (MMP) were also investigated. The mechanism was confirmed by PI3K inhibitor and NOS inhibitor in normal or eNOS siRNA transfection HBMEc. Vitexin significantly reduced LDH, Caspase 3 level, alleviated inflammation, also could maintain BBB integrity, increased tight junction proteins expression and inhibited MMP. The mechanism is related to reduction of intracellular NO and ONOO^-, regulated eNOS, iNOS activity. Vitexin significantly preserved eNOS phosphorylation in response to the activated Akt. Moreover, combined with PI3K inhibitor or low dosage of NOS inhibitor, totally abolished Vitexin-induced eNOS phosphorylation, the protected effect was also attenuated, but still significantly between model cells. However, combined with high dosage NOS inhibitor which both inhibited the eNOS phosphorylation and iNOS, the protected effect of Vitexin was abrogated. In addition, eNOS silencing cells were used to further clarify the regulatory role of Vitexin on iNOS. Our findings showed that Vitexin could play a protective role in I/R-induced brain endothelial permeability by simultaneously increase eNOS phosphorylation and inhibit iNOS.

Neuroanesthesiology Update

This review provides a summary of the literature pertaining to the perioperative care of neurosurgical patients and patients with neurological diseases. General topics addressed in this review include general neurosurgical considerations, stroke, traumatic brain injury, neuromonitoring, neurotoxicity, and perioperative disorders of cognitive function.

Involvement of angiotensin-(1-7) in the neuroprotection of captopril against focal cerebral ischemia

Accumulating evidence suggests that brain angiotensin-converting enzyme (ACE)/angiotensin II/angiotensin II type I receptor axis is activated and thus contributes to the neuronal injury during ischemic stroke. Conversely, inhibition of this axis using centrally active ACE inhibitor captopril was proven neuroprotective in rodents with focal cerebral ischemia. Interestingly, captopril was able to increase angiotensin-(1-7) [Ang-(1-7)] levels in the peripheral organs. As the main component of the alternative renin-angiotensin system axis in the brain, Ang-(1-7) was revealed to protect against focal cerebral ischemia via a MAS1 receptor-dependent manner. Based on this evidence, we hypothesized that Ang-(1-7) might contribute to the neuroprotection of captopril during ischemic stroke. In this study, we evaluated this hypothesis using a rat model of focal cerebral ischemia. We revealed that brain ACE2 activity and Ang-(1-7) levels were significantly elevated following captopril treatment in rats with focal cerebral ischemia. More importantly, we showed that the neuroprotection provided by captopril was partially reversed by A-779, an antagonist for Ang-(1-7) receptor MAS1, indicating that Ang-(1-7) was involved in the neuroprotection of captopril. These findings have uncovered new mechanisms by which captopril protects against focal cerebral ischemia and further suggest that captopril may have practical clinical use for stroke prevention and treatment in addition to its antihypertensive effect.