Modified Citrus Pectin Alleviates Cerebral Ischemia/Reperfusion Injury by Inhibiting NLRP3 Inflammasome Activation via TLR4/NF-ĸB Signaling Pathway in Microglia.

Background: Galectin-3 acts as a mediator of microglial inflammatory response following stroke injury. However, it remains unclear whether inhibiting galectin-3 protects against cerebral ischemia/reperfusion injury. We aimed to investigate the neuroprotective effects of modified citrus pectin (MCP, a galectin-3 blocker) in ischemic stroke and underlying mechanisms. Methods: The middle cerebral artery occlusion/reperfusion (MCAO/R) model in C57BL/6J mice and oxygen-glucose deprivation/reoxygenation (ODG/R) model in neuronal (HT-22) and microglial (BV-2) cells were utilized in the following experiments: 1) the neuroprotective effects of MCP with different concentrations were evaluated in vivo and in vitro through measuring neurological deficit scores, brain water content, infarction volume, cell viability, and cell apoptosis; 2) the mechanisms of its neuroprotection were explored in mice and microglial cells through detecting the expression of NLRP3 (NOD-like receptor 3) inflammasome-related proteins by immunofluorescence staining and Western blotting analyses. Results: Among the tested concentrations, 800 mg/kg/d MCP in mice and 4 g/L MCP in cells, respectively, showed in vivo and in vitro neuroprotective effects on all the tests, compared with vehicle group. First, MCP significantly reduced neurological deficit scores, brain water content and infarction volume, and alleviated cell injury in the cerebral cortex of MCAO/R model. Second, MCP increased cell viability and reduced cell apoptosis in the neuronal OGD/R model. Third, MCP blocked galectin-3 and decreased the expression of TLR4 (Toll-like receptor 4)/NF-κBp65 (nuclear factor kappa-B)/NLRP3/cleaved-caspase-1/IL-1ß (interleukin-1ß) in microglial cells. Conclusion: This is the first report that MCP exerts neuroprotective effects in ischemic stroke through blocking galectin-3, which may be mediated by inhibiting the activation of NLRP3 inflammasome via TLR4/NF-κB signaling pathway in microglia.

Early neurological deterioration after intravenous thrombolysis of anterior vs posterior circulation stroke: a secondary analysis of INTRECIS.

Anterior circulation stroke (ACS) differs from posterior circulation stroke (PCS) in many ways, but it remains unclear whether there is any difference in early neurological deterioration (END) in two stroke territories. We compared post-thrombolytic END between ACS and PCS based on the data from INTRECIS. We screened patients receiving intravenous 0.9 mg/kg alteplase within 4.5 h in the INTRECIS cohort. According to stroke territory, patients were divided into ACS and PCS groups. The primary outcome was incidence of END, which was defined as an increase in NIHSS score ≥ 4 or death within 24 h from baseline. The secondary outcomes were associated factors of END and 90-day modified Rankin Scale (mRS) distribution. Overall, 1194 patients were enrolled in this study: 942 in ACS group and 252 in PCS group. There was no significant difference in the incidence of END between two groups (3.8% vs 5.2%, adjusted p = 0.406). Atrial fibrillation (adjusted p = 0.012) and TOAST classification (adjusted p = 0.009) were associated with END in ACS, while hypertension history (adjusted p = 0.046) and baseline NIHSS score (adjusted p = 0.011) with END in PCS. END was associated with worse outcome on 90-day mRS in ACS and PCS (adjusted p < 0.001). Based on a prospective nationwide cohort, we provided first report for similar incidence, but different risk factors of post-thrombolytic END in ACS vs PCS patients.Trial Registration-URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02854592.

Association of Serum Biomarkers With Post-Thrombolytic Symptomatic Intracranial Hemorrhage in Stroke: A Comprehensive Protein Microarray Analysis From INTRECIS Study.

BACKGROUND: Symptomatic intracranial hemorrhage (sICH) after intravenous thrombolysis is closely related to the poor outcome of stroke. AIMS: To determine the serum biomarkers associated with sICH based on the INTRECIS study. METHODS: Enrolled patients with sICH and without any ICH were matched by propensity score matching with the ratio of 1:1. Preset 49 biomarkers were measured by protein microarray analysis. Gene Ontology and Pathway Enrichment Analysis and protein-protein interaction network (PPI) were analyzed in the identified biomarkers. RESULTS: Of the consecutive 358 patients, eight patients occurred with sICH, which was assigned as an sICH group, while eight matched patients without any ICH were assigned as a Non-sICH group. A total of nine biomarkers were found significantly different between groups, among which the levels of interferon (IFN)-γ and interleukin (IL)-4 were higher, while the levels of C-reactive protein (CRP), glial cell line-derived neurotrophic factor (GDNF), insulin-like growth factor-binding protein (IGFBP)-6, lymphatic vessel endothelial hyaluronan receptor (LYVE)-1, matrix metalloprotein (MMP)-2, plasminogen activator inhibitor (PAI)-1, and platelet-derived growth factor (PDGF)-AA were lower in the sICH group compared with those in the Non-sICH group. CONCLUSIONS: Our finding indicated that baseline serum CRP, GDNF, IFN-γ, IGFBP-6, IL-4, LYVE-1, MMP-2, PAI-1, and PDGF-AA levels were associated with post-thrombolytic sICH in stroke.

ZW290 Increases Cold Tolerance by Inducing Thermogenesis via the Upregulation of Uncoupling Protein 1 in Brown Adipose Tissue In Vitro and In Vivo.

To provide molecular evidence on the thermogenic mechanism of primary brown adipocytes, western blot analysis was used to detect brown adipose tissue (BAT)-specific gene expressions. BAT protects the mammals from hypothermia injury with a large amount of mitochondria and high expression of uncoupling Protein 1 (UCP1), which is the vital protein to determine the heat production in BAT. In our previous study, the compound ZW290 (the structure shown in Fig. 1) was obtained by molecular docking with a UCP1 inducer. In the present study, ZW290 not only significantly upregulated the expression of UCP1 protein (p < 0.01) and its related signaling pathway in the primary brown adipocytes, but also remarkably decreased the mitochondrial membrane potential and the concentration of adenosine triphosphate (ATP) (p < 0.01). Kunming (KM) mice were kept under acute cold exposure (-20°C) to evaluate the preventive and protective effects of ZW290 on cold injury, and revealed its regulating mechanism in vitro. The rectal and body temperatures of ZW290-treated mice were significantly higher than those of the control (or model) group both at room temperature and at -20°C (p < 0.001). Hematoxylin-eosin (HE) staining and immunohistochemistry indicated that ZW290 notably decreased the size of lipid droplets in BAT and increased the content of mitochondria and the expression of UCP1 in BAT and white adipose tissue (WAT). Furthermore, the survival rate showed that ZW290 could prolong the overall survival of mice. Therefore, we obtained the conclusion that ZW290 might transform energy into heat by inhibiting ATP synthesis and increasing the expression of UCP1. Additionally, ZW290 may enhance cold tolerance by increasing heat production through increasing the content of mitochondria and the expression of UCP1 in BAT and WAT.

Caffeoylquinic Acid Derivatives Protect SH-SY5Y Neuroblastoma Cells from Hydrogen Peroxide-Induced Injury Through Modulating Oxidative Status.

Oxidative stress has been confirmed as a contribution to the pathogenesis and pathophysiology of many neurological disorders such as Alzheimer's disease and Parkinson's disease. Caffeoylquinic acids (CQAs) are considered to have anti-oxidative stress ability in a previous study, but the structure-activity relationships (SARs) of CQAs in neuroprotective effects are still unclear. In the present study, we primarily expound the SARs of CQAs in counteracting H2O2-induced injury in SH-SY5Y cells. We found that CQAs (1-10) represented the protection of SH-SY5Y cells against H2O2-induced injury in varying degrees and malonyl groups could obviously increase the anti-oxidative stress ability of CQAs. Intensive studies of 4,5-O-dicaffeoyl-1-O-(malic acid methyl ester)-quinic acid (MDCQA) indicated that the mechanisms could potentially involve activation of endogenous antioxidant enzymes and the regulation of the phosphorylation of MAPKs and AKT. In conclusion, MDCQA could serve as a neuroprotective agent with a potential to attenuate oxidative stress.

Neuroprotective effects of Kukoamine B against hydrogen peroxide-induced apoptosis and potential mechanisms in SH-SY5Y cells.

Oxidative stress mediates the cell damage in several neurodegenerative diseases, including multiple sclerosis, Alzheimer's disease (AD) and Parkinson's disease (PD). This study aimed at investigating the protective effects of Kukoamine B (KuB) against hydrogen peroxide (H2O2) induced cell injury and potential mechanisms in SH-SY5Y cells. Our results revealed that treatment with KuB prior to H2O2 exposure effectively increased the cell viability, and restored the mitochondria membrane potential (MMP). Furthermore, KuB enhanced the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) and decreased the malondialdehyde (MDA) content. Moreover, KuB minimized the ROS formation and inhibited mitochondria-apoptotic pathway, MAPKs (p-p38, p-JNK, p-ERK) pathways, but activated PI3K-AKT pathway. In conclusion, we believed that KuB may potentially serve as an agent for prevention of several human neurodegenerative and other disorders caused by oxidative stress.

Compound MQA, a Caffeoylquinic Acid Derivative, Protects Against NMDA-Induced Neurotoxicity and Potential Mechanisms In Vitro.

AIMS: Compound MQA (1,5-O-dicaffeoyl-3-O-[4-malic acid methyl ester]-quinic acid) is a natural derivative of caffeoylquinic acid isolated from Arctium lappa L. roots. However, we know little about the effects of MQA on the central nervous system. This study aims to investigate the neuroprotective effects and underlying mechanisms of MQA against the neurotoxicity of N-methyl-d-aspartate (NMDA). METHODS AND RESULTS: Pretreatment with MQA attenuated the loss of cell viability after SH-SY5Y cells treated with 1 mM NMDA for 30 min by MTT assay. Hoechst 33342 and Annexin V-PI double staining showed that MQA inhibited NMDA-induced apoptosis. In addition to preventing Ca(2+) influx, the potential mechanisms are associated with increases in the Bcl-2/Bax ratio, attenuation of cytochrome c release, caspase-3, caspase-9 activities, and expressions. Also, MQA inhibited NMDA-induced phosphorylation of ERK1/2, p38, and JNK1/2. Furthermore, deactivation of CREB, AKT, and GSK-3ß, upregulation of GluN2B-containing NMDA receptors (NMDARs), and downregulation of GluN2A-containing NMDARs were significantly reversed by MQA treatment. Computational docking simulation indicates that MQA possesses a well affinity for NMDARs. CONCLUSION: The protective effects of MQA against NMDA-induced cell injury may be mediated by blocking NMDARs. The potential mechanisms are related with mitochondrial apoptosis, ERK-CREB, AKT/GSK-3ß, p38, and JNK1/2 pathway.

Kukoamine B, an amide alkaloid, protects against NMDA-induced neurotoxicity and potential mechanisms in vitro.

A major cause of cerebral ischemia is overactivation of the N-methyl-D-aspartate receptors (NMDARs). Therefore, NMDAR antagonists are needed for the treatment of cerebral ischemia. In our research, KuB protected the SH-SY5Y cells against NMDA-induced injury, apoptosis, LDH release and MMP loss. In addition, KuB could decrease MDA levels while increasing SOD activity. Meanwhile, KuB decreased NADPH oxidase-mediated ROS production, inhibited Ca(2+) influx, and increased the Bcl-2/Bax ratio. Furthermore, KuB not only down-regulated expression of the NR2B subunit of NMDAR but also actively modulated expression of the signaling molecules downstream of NR2B, including p-ERK, p-CREB, p-AKT and SAPKs. Finally, docking results showed that KuB had a high affinity for NR2B-containing NMDARs. Therefore, we conclude that KuB protected the SH-SY5Y cells from NMDA-induced injury likely by antagonizing NMDARs and reducing oxidative stress.

Anti-proliferative and pro-apoptotic activities of Alpinia oxyphylla on HepG2 cells through ROS-mediated signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Fructus Alpiniae oxyphyllae (A. oxyphylla) is a traditional herb which is widely used in East Asian for the treatment of dyspepsia, diarrhea, abdominal pain, poor memory, inflammatory conditions and cancer. MATERIALS AND METHODS: The cytotoxic activities of ethanol extract (EE) and five extract layers including petroleum ether (PE), dichloromethane (DCLM), acetoacetate (EtOAc), n-Butanol (n-Bu) and water fractions (WF) of A. oxyphylla were tested on HepG2, SW480, MCF-7, K562 and HUVEC cell lines using MTT assay and LDH release assay. The component analysis was performed on HPLC with gradient elution. Hoechst 33342 staining, DCFH-DA fluorescence microscopy, flow cytometry analysis, western blot and migration assays were carried out to determine the anti-cancer mechanisms of PE. RESULTS: MTT analysis showed that EE, PE and DCLM could inhibit cell proliferation on HepG2, SW480, MCF-7, K562 and HUVEC cell lines, especially PE fraction. HPLC analysis pointed out five main components which may contribute to the anti-proliferative activity of PE. Further study showed that PE increased LDH release, induced apoptosis, disrupted mitochondrial membrane potential and elevated intracellular reactive oxygen species (ROS) in HepG2 cells, whereas the antioxidant N-acetyl-l-cysteine (NAC) prevented PE-induced ROS generation. The results of western blot revealed that PE induced apoptosis in HepG2 cells by enhancing Bax/Bcl-2 ratio, increasing cytochrome c in cytosol and activating caspase-3/9. Meanwhile, high levels of ROS could induce DNA damage-mediated protein expression, AKT, ERK inactivation and SAPKs activation. Furthermore, PE conspicuously blocked the migration of HUVEC cells. CONCLUSION: The present results demonstrated that PE induced apoptosis in HepG2 cells may be via a ROS-mediated signaling pathway.

Neuroprotection by Kukoamine A against oxidative stress may involve N-methyl-D-aspartate receptors.

BACKGROUND: Accumulative evidences have indicated that oxidative-stress and over-activation of N-methyl-d-aspartate receptors (NMDARs) are important mechanisms of brain injury. This study investigated the neuroprotection of Kukoamine A (KuA) and its potential mechanisms. METHODS: Molecular docking was used to discover KuA that might have the ability of blocking NMDARs. Furthermore, the MTT assay, the measurement of LDH, SOD and MDA, the flow cytometry for ROS, MMP and Annexin V-PI double staining, the laser confocal microscopy for intracellular Ca2+ and western-blot analysis were employed to evaluate the neuroprotection of KuA. RESULTS: KuA attenuated H2O2-induced cell apoptosis, LDH release, ROS production, MDA level, MMP loss, and intracellular Ca2+ overload (both induced by H2O2 and NMDA), as well as increased the SOD activity. In addition, it could modulate the apoptosis-related proteins (Bax, Bcl-2, p53, procaspase-3 and procaspase-9), the SAPKs (ERK, p38), AKT, CREB, NR2A and NR2B expression. CONCLUSIONS: All the results indicated that KuA has the ability of anti-oxidative stress and this effect may partly via blocking NMDARs in SH-SY5Y cells. GENERAL SIGNIFICANCE: KuA might have the potential therapeutic interventions for brain injury.

An efficient and secure medical image protection scheme based on chaotic maps.

Recently, the increasing demand for telemedicine services has raised interest in the use of medical image protection technology. Conventional block ciphers are poorly suited to image protection due to the size of image data and increasing demand for real-time teleradiology and other online telehealth applications. To meet this challenge, this paper presents a novel chaos-based medical image encryption scheme. To address the efficiency problem encountered by many existing permutation-substitution type image ciphers, the proposed scheme introduces a substitution mechanism in the permutation process through a bit-level shuffling algorithm. As the pixel value mixing effect is contributed by both the improved permutation process and the original substitution process, the same level of security can be achieved in a fewer number of overall rounds. The results indicate that the proposed approach provides an efficient method for real-time secure medical image transmission over public networks.

Novel miniature mobile cardiac catheterization laboratory for critical cardiovascular disease following natural disasters: a feasibility study.

BACKGROUND: Natural disasters have been frequent in recent years. Effective treatment of patients with cardiovascular disease following natural disasters is an unsolved problem. We aimed to develop a novel miniature mobile cardiac catheterization laboratory (Mini Mobile Cath Lab) to provide emergency interventional services for patients with critical cardiovascular disease following natural disasters. A feasibility study was performed by testing the Mini Mobile Cath Lab on dogs with ST-elevation myocardial infarction (STEMI) model in a hypothetical natural-disaster-stricken area. METHODS: The Mini Mobile Cath Lab was transported to the hypothetical natural-disaster-stricken area by truck. Coronary angiography and primary percutaneous coronary intervention (PCI) were performed on six dogs with STEMI model. The transportation and transformation of the Mini Mobile Cath Lab were monitored and its functioning was evaluated through the results of animal experiments. RESULTS: The Mini Mobile Cath Lab could be transported by truck at an average speed of 80 km/h on mountain roads during daytime in the winter, under conditions of light snow (-15°C to -20°C/-68°F to -59°F). The average time required to prepare the Mini Mobile Cath Lab after transportation, in a wetland area, was 30 minutes. Coronary angiography, and primary PCI were performed successfully. CONCLUSION: This preliminary feasibility study of the use of the Mini Mobile Cath Lab for emergency interventional treatment of dogs with STEMI indicated that it may perform well in the rescue of critical cardiovascular disease following natural disasters.

A chaos-based digital image encryption scheme with an improved diffusion strategy.

Chaos-based image cipher has been widely investigated over the last decade or so to meet the increasing demand for real-time secure image transmission over public networks. In this paper, an improved diffusion strategy is proposed to promote the efficiency of the most widely investigated permutation-diffusion type image cipher. By using the novel bidirectional diffusion strategy, the spreading process is significantly accelerated and hence the same level of security can be achieved with fewer overall encryption rounds. Moreover, to further enhance the security of the cryptosystem, a plain-text related chaotic orbit turbulence mechanism is introduced in diffusion procedure by perturbing the control parameter of the employed chaotic system according to the cipher-pixel. Extensive cryptanalysis has been performed on the proposed scheme using differential analysis, key space analysis, various statistical analyses and key sensitivity analysis. Results of our analyses indicate that the new scheme has a satisfactory security level with a low computational complexity, which renders it a good candidate for real-time secure image transmission applications.