Advancing stroke therapy: innovative approaches with stem cell-derived extracellular vesicles.

Stroke is a leading cause of mortality and long-term disability globally, with acute ischemic stroke (AIS) being the most common subtype. Despite significant advances in reperfusion therapies, their limited time window and associated risks underscore the necessity for novel treatment strategies. Stem cell-derived extracellular vesicles (EVs) have emerged as a promising therapeutic approach due to their ability to modulate the post-stroke microenvironment and facilitate neuroprotection and neurorestoration. This review synthesizes current research on the therapeutic potential of stem cell-derived EVs in AIS, focusing on their origin, biogenesis, mechanisms of action, and strategies for enhancing their targeting capacity and therapeutic efficacy. Additionally, we explore innovative combination therapies and discuss both the challenges and prospects of EV-based treatments. Our findings reveal that stem cell-derived EVs exhibit diverse therapeutic effects in AIS, such as promoting neuronal survival, diminishing neuroinflammation, protecting the blood-brain barrier, and enhancing angiogenesis and neurogenesis. Various strategies, including targeting modifications and cargo modifications, have been developed to improve the efficacy of EVs. Combining EVs with other treatments, such as reperfusion therapy, stem cell transplantation, nanomedicine, and gut microbiome modulation, holds great promise for improving stroke outcomes. However, challenges such as the heterogeneity of EVs and the need for standardized protocols for EV production and quality control remain to be addressed. Stem cell-derived EVs represent a novel therapeutic avenue for AIS, offering the potential to address the limitations of current treatments. Further research is needed to optimize EV-based therapies and translate their benefits to clinical practice, with an emphasis on ensuring safety, overcoming regulatory hurdles, and enhancing the specificity and efficacy of EV delivery to target tissues.

Anti-inflammatory Effect of Batroxobin Combined With Anticoagulation in Patients With Cerebral Venous Thrombosis.

Inflammation is pivotal in the pathogenesis and development of cerebral venous thrombosis (CVT). Herein, we aimed to assess the anti-inflammatory effects of batroxobin combined with anticoagulation in CVT. Participants were categorized into the batroxobin group (batroxobin combined with anticoagulation) and the control group (anticoagulation only). Regression analysis was employed to explore the association between the number of episodes of batroxobin administration and the fluctuation of inflammatory indicators, as well as the proportion of patients with inflammatory indicators that were reduced after batroxobin use. Twenty-three cases (age: 39.9 ± 13.8 years, female: 39.1%) in the batroxobin group and 36 cases (40.3 ± 9.6 years, 52.8%) in the control group were analyzed. Compared to the control group, batroxobin combined with anticoagulation significantly decreased fibrinogen (P < .001), platelet-lymphocyte ratio (PLR) (P = .016) and systemic immune-inflammation index (SII) (P = .008), and increased the proportion of the patients with lower fibrinogen (P < .001), neutrophil-lymphocyte ratio (NLR) (P = .005), PLR (P = .026), and SII (P = .006). Linear analysis showed that as the number of episodes of batroxobin administration increased, the fibrinogen (P < .001), the PLR (P = .001), and the SII (P = .020) significantly decreased. Logistic regression analysis showed as the number of episodes of batroxobin administration increased, the ratio of the patients with decreased NLR (P = .008) and PLR (P = .015), as well as SII (P = .013), significantly increased. Batroxobin could decrease NLR, PLR, and SII in CVT. The effect was related to the number of episodes of batroxobin administration. Besides reducing fibrinogen and indirect thrombolysis effects, this may be another critical benefit of batroxobin for CVT.

The possible causal relationship between COVID-19 and imaging markers of cerebral small vessel disease: a Mendelian randomization study.

OBJECTIVES: Observational studies have suggested that SARS-CoV-2 infection may increase the burden of cerebral small vessel disease (CSVD). This study aims to explore the causal correlation between COVID-19 and the imaging markers of CSVD using Mendelian randomization (MR) methods. METHODS: Summary-level genome-wide association study (GWAS) statistics for COVID-19 susceptibility, hospitalization, and severity were utilized as proxies for exposure. Large-scale meta-analysis GWAS data on three neuroimaging markers of white matter hyperintensity, lacunar stroke, and brain microbleeds, were employed as outcomes. Our primary MR analysis employed the inverse variance weighted (IVW) approach, supplemented by MR-Egger, weighted median, and MR-PRESSO methods. We also conducted multivariable MR analysis to address confounding bias and validate the robustness of the established causal estimates. Comprehensive sensitivity analyses included Cochran's Q test, Egger-intercept analysis, MR-PRESSO, and leave-one-out analysis. RESULTS: The MR analysis revealed a significant causal correlation between the severity of COVID-19 and an increased risk of lacunar stroke, as demonstrated by the IVW method (ORivw = 1.08, 95% CI: 1.03-1.16, pivw = 0.005, FDR = 0.047). Nevertheless, no causal correlations were observed between COVID-19 susceptibility or hospitalization and any CSVD imaging markers. The robustness and stability of these findings were further confirmed by multivariable MR analysis and comprehensive sensitivity analyses. DISCUSSION: This study provides compelling evidence of a potential causal effect of severe COVID-19 on the incidence of lacunar stroke, which may bring fresh insights into the understanding of the comorbidity between COVID-19 and CSVD.

The causal relationship between sarcopenia-related traits and ischemic stroke: Insights from univariable and multivariable Mendelian randomization analyses.

AIMS: The causal relationship between sarcopenia-related traits and ischemic stroke (IS) remains poorly understood. This study aimed to explore the causal impact of sarcopenia-related traits on IS and to identify key mediators of this association. METHODS: We conducted univariable, multivariable two-sample, and two-step Mendelian randomization (MR) analyses using genome-wide association study (GWAS) data. This included data for appendicular lean mass (ALM), hand grip strength (HGS), and usual walking pace (UWP) from the UK Biobank, and IS data from the MEGASTROKE consortium. Additionally, 21 candidate mediators were analyzed based on their respective GWAS data sets. RESULTS: Each 1-SD increase in genetically proxied ALM was associated with a 7.5% reduction in the risk of IS (95% CI: 0.879-0.974), and this correlation remained after controlling for levels of physical activity and adiposity-related indices. Two-step MR identified that six mediators partially mediated the protective effect of higher ALM on IS, with the most significant being coronary heart disease (CHD, mediating proportion: 39.94%), followed by systolic blood pressure (36.51%), hypertension (23.87%), diastolic blood pressure (15.39%), type-2 diabetes mellitus (T2DM, 12.71%), and low-density lipoprotein cholesterol (7.97%). CONCLUSION: Our study revealed a causal protective effect of higher ALM on IS, independent of physical activity and adiposity-related indices. Moreover, we found that higher ALM could reduce susceptibility to IS partially by lowering the risk of vascular risk factors, including CHD, hypertension, T2DM, and hyperlipidemia. In brief, we elucidated another modifiable factor for IS and implied that maintaining sufficient muscle mass may reduce the risk of such disease.

Rapid purification and scale-up of tilianin using counter-current chromatography with rectangular horizontal tubing.

In counter-current chromatography (CCC), linear scale-up is an ideal amplification strategy. However, when transferring from analytical to predictable preparative processes with high throughput, linear scale-up would be challenging due to limitations imposed by differences in instrument parameters, such as gravitational forces, tubing cross-section area, tubing length, column volume and flow rate. Some effective scale-up strategies have been studied for different instrument parameters, but so far, these scale-up works have only been tested on standard circular (SC) tubing. The previous research of our group found that rectangular horizontal (RH) tubing can double the separation efficiency compared with conventional SC tubing, and has industrial production potential. This paper used the separation of tilianin from Dracocephalum moldavica L. as an example to demonstrate how to scale up the optimized process from analytical SC tubing to preparative RH tubing. After systematic optimization of solvent systems, sample concentration and flow rate on the analytical CCC, the optimized parameters obtained were successfully transferred to the preparative CCC. The results showed that a crude sample of 2.07 g was successfully separated using a solvent system of n-hexane - ethyl acetate - ethanol - water (1:4:1:5, v/v/v/v) in reversed phase mode, and the three consecutive separations produced a total of 380 mg tilianin in 75 min with high purities of 98.3%, as analyzed by HPLC. The total throughput achieved from the analytical to semi-preparative scale was improved by 138 times (from 12 mg/h to 1.66 g/h), while the column volume was increased by only 46.5 times (from 15.5 mL to 720 mL). This is the successful application of CCC for the separation and purification of tilianin. Given that SC tubing is the traditional configuration for CCC columns, this study is a necessary step to prove the applicability of RH tubing columns for routine use and potential large-scale industrial applications.

A perfusion territory shift attributable solely to the secondary collaterals in moyamoya patients: a potential risk factor for preoperative hemorrhagic stroke revealed by t-ASL and 3D-TOF-MRA.

OBJECTIVE: The authors conducted a study to noninvasively and nonradioactively reveal moyamoya disease (MMD) intracerebral perfusion and perfusion territory supplied by the unilateral internal carotid artery (ICA) and external carotid artery (ECA) and bilateral vertebral arteries (VAs) before surgery and to further identify risk factors for preoperative hemorrhage in adult MMD. METHODS: Forty-three consecutive adult patients with bilateral MMD underwent unenhanced T1-weighted MRI, territorial arterial spin labeling (t-ASL), and unenhanced 3D time-of-flight MRA (3D-TOF-MRA). Clinical factors, including age, sex, hypertension, diabetes mellitus, hyperlipidemia, current smoking status, and history of taking aspirin, were gathered and stratified. Univariate logistic regression analyses were used to examine the relationship between various risk factors and the occurrence of preoperative hemorrhage. Stepwise multivariate logistic regression analyses were used to determine independent risk factors of preoperative hemorrhage in MMD. RESULTS: Among the 86 MMD hemispheres, t-ASL revealed 137 perfusion territory shifts in 79 hemispheres. Five distinct categories of perfusion territory shifts were observed on t-ASL maps. The subtypes of perfusion territory shift on t-ASL maps were further subdivided into 2 different categories, group A and group B, in combination with findings on 3D-TOF-MRA. A perfusion territory shift attributable solely to the secondary collaterals was a potential independent risk factor for preoperative hemorrhage (p = 0.026; 95% CI 1.201-18.615; OR 4.729). After eliminating the influence of the secondary collaterals, the primary collaterals had no significant effect on the risk of preoperative hemorrhage (p = 0.182). CONCLUSIONS: t-ASL could reveal comprehensive MMD cerebral blood perfusion and the vivid perfusion territory shifts fed by the unilateral ICA and ECA and bilateral VAs in a noninvasive, straightforward, nonradioactive, and nonenhanced manner. 3D-TOF-MRA could subdivide t-ASL perfusion territory shifts according to their shunt arteries. A perfusion territory shift attributable to the secondary collaterals is a potential independent risk factor for preoperative hemorrhage in MMD patients. A perfusion territory shift fed by the primary collaterals may not have a strong effect on preoperative hemorrhage in MMD patients. These findings make the combined modalities of t-ASL and 3D-TOF-MRA a feasible tool for MMD disease assessment, management, and surgical strategy planning.

Prognostic value of estrogen receptor in WHO Grade III meningioma: a long-term follow-up study from a single institution.

OBJECTIVE Malignant meningioma is rare and classified as Grade III in the WHO classification of CNS tumors. However, the presence of estrogen receptor (ER) in WHO Grade III meningiomas and its correlation with patients' outcomes are still unclear. In this single-center cohort study, the authors analyzed clinical features, treatment, and prognosis of these malignant tumors in patients with long-term follow-up. METHODS A total of 87 patients who were pathologically diagnosed with WHO Grade III meningiomas between 2003 and 2008 were enrolled in this study and followed for at least 7 years. Clinical information was collected to analyze the factors determining the prognosis. RESULTS Twelve patients with rhabdoid, 12 with papillary, and 63 with anaplastic meningioma were included. The mean progression-free survival (PFS) and overall survival (OS) were 56.2 ± 49.8 months and 68.7 ± 47.4 months, respectively. No significant differences were observed among the 3 histological subtypes in either PFS (p = 0.929) or OS (p = 0.688). Patients who received gross-total resection had a longer PFS (p = 0.001) and OS (p = 0.027) than those who received subtotal resection. Adjuvant radiotherapy was associated with OS (p = 0.034) but not PFS (p = 0.433). Compared with primary meningiomas, patients with recurrent disease had worse PFS (p < 0.001). For patients who had malignant transformations, the prognosis was poorer than for patients without malignant transformations for both PFS (p = 0.002) and OS (p = 0.019). ER-positive patients had a significantly worse prognosis than ER-negative patients regarding both PFS (p = 0.003) and OS (p < 0.001), whereas no association between progesterone receptor and patients' outcomes was observed. Multivariate analysis demonstrated that ER expression was an independent prognostic factor for both PFS (p = 0.008) and OS (p < 0.001). CONCLUSIONS This retrospective study showed that patients with meningioma with ER-positive expression had a much worse prognosis than those with ER weak-positive or ER-negative status. The results demonstrated that ER is an independent prognostic factor for both PFS and OS of patients with WHO Grade III meningioma. The authors also found that more radical resection of the tumor, as well as postoperative radiotherapy, may prolong patients' survival time.

KLF4 is a tumor suppressor in anaplastic meningioma stem-like cells and human meningiomas.

Meningiomas are the most common primary tumors in central nervous system. While recent studies have revealed genetic clues to lower grade human meningiomas, the molecular determinants driving the progression and recurrence of anaplastic meningioma, the most malignant subtype with a low prevalence but high morbidity, are still poorly understood. It has been proposed that high recurrence rates of malignant meningiomas are linked to cancer stem cells. Indeed, tumor stem-like cells have been isolated from various meningioma subtypes, but never been obtained from anaplastic meningioma. In this study, we successfully isolated stem-like cells from human anaplastic meningioma. These cells are capable of forming spheres and initiating xenograft tumors that recapitulate anaplastic meningioma phenotypes, and thus could serve as an in vitro model for malignant meningiomas. KLF4, a transcription factor known for its role in stemness maintenance, was identified as one of the most frequently mutated genes in the benign secretory meningioma. Interestingly, we found that KLF4 is downregulated in anaplastic meningioma compared with low-grade meningioma subtypes. By manipulating KLF4 expression in anaplastic meningioma stem-like cells, we demonstrated that KLF4 acts as a tumor suppressor during malignant progression in meningioma, affecting apoptosis, proliferation, invasion, and cell cycle. These results suggest a potential therapeutic value of KLF4 for clinical intervention of anaplastic meningioma.