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Background and Purpose: In ischemic stroke, breakdown of the blood-brain barrier (BBB) aggravates brain damage. Endothelial detachment contributes to BBB disruption and neurovascular dysfunction, but its regulation in stroke has yet to be clarified. We investigated the function of NMMHC IIA (nonmuscle myosin heavy chain IIA) in the endothelium on BBB breakdown and its potential mechanisms. Methods: Endothelial conditional knockdown NMMHC IIA ( Myh9 ECKD ) was constructed in vivo and in vitro, and its role was explored in middle cerebral artery occlusion/reperfusion–injured mice and oxygen-glucose deprivation/reoxygenation–injured brain microvascular endothelial cells. The degree of brain injury was analyzed using staining (2,3,5-triphenyltetrazolium chloride, hematoxylin, and eosin) and electron microscopy. BBB breakdown was investigated with leakage of Evans Blue dye and expression of TJs (tight junctions) and MMP (matrix metallopeptidase)-2/9. Transcriptomics for enrichment analysis was adopted to explore the potential downstream signaling pathways of NMMHC IIA involved in middle cerebral artery occlusion/reperfusion–induced BBB dysfunction. Results: NMMHC IIA expression was upregulated in endothelial cells after cerebral ischemia/reperfusion injury. Myh9 ECKD mice exhibited improvement in endothelial barrier hyperpermeability and TJs integrity stimulated by cerebral ischemia/reperfusion. Blebbistatin (NMMHC II inhibitor) treatment exerted the same effect. Transcriptomics showed that NMMHC IIA was involved in regulating various BBB-related genomic changes in the middle cerebral artery occlusion/reperfusion model, and NMMHC IIA was confirmed to significantly modulate Hippo and peroxisome proliferator-activated receptor gamma/nuclear factor-kappa B signaling pathways, which are closely related to BBB damage. Conclusions: Our findings provide some new insights into how NMMHC IIA contributes to maintaining the integrity of the cerebral endothelial barrier. NMMHC IIA could be a potential therapeutic target for ischemic stroke.

Screening bioactive compounds from natural product and its preparations using capillary electrophoresisBioactive ingredients of natural products can protect human body from harm, as well as prevent and treat disease. Screening bioactive compounds from natural products is attracting particular attention. It is a great challenge to separate and detect the active compounds from complex matrix natural products. CE plays a vital role in screening active compounds because of its unique features such as high-efficiency separation, short-analysis time, minimal sample consumption, and ease to realize automatization etc. Additionally, CE has been developed various modes owing to its abundant advantages in analysis and separation of compounds. The purpose of this work is to review previous developments and applications of CE in screening bioactive compounds derived from natural products from 2007 to 2017. This review does not only summarize the traditional methods of detecting active ingredients but also briefly introduces some novel assays. The trends in the application of CE in active compounds screening are addressed in the article.

A novel method of on-line 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate)-Capillary Electrophoresis-Diode Array Detector (on-line ABTS+-CE-DAD) was developed to screen the major antioxidants from complex herbal medicines. ABTS+, one of well-known oxygen free radicals was firstly integrated into the capillary. For simultaneously detecting and separating ABTS+ and chemical components of herb medicines, some conditions were optimized. The on-line ABTS+-CE-DAD method has successfully been used to screen the main antioxidants from Shuxuening injection (SI), an herbal medicines injection. Under the optimum conditions, nine ingredients of SI including clitorin, rutin, isoquercitrin, Quercetin-3-O-D-glucosyl]-(1-2)-L-rhamnoside, kaempferol-3-O-rutinoside, kaempferol-7-O-β-D-glucopyranoside, apigenin-7-O-Glucoside, quercetin-3-O-[2-O-(6-O-p-hydroxyl-E-coumaroyl)-D-glucosyl]-(1-2)-L-rhamnoside, 3-O-{2-O-[6-O-(p-hydroxyl-E-coumaroyl)-glucosyl]}-(1-2) rhamnosyl kaempfero were separated and identified as the major antioxidants. There is a linear relationship between the total amount of major antioxidants and total antioxidative activity of SI with a linear correlation coefficient of 0.9456. All the Relative standard deviations of recovery, precision and stability were below 7.5%. Based on these results, these nine ingredients could be selected as combinatorial markers to evaluate quality control of SI. It was concluded that on-line ABTS+-CE-DAD method was a simple, reliable and powerful tool to screen and quantify active ingredients for evaluating quality of herbal medicines.

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