The association between proactive personality and interprofessional learning readiness in nursing students: The chain medication effects of perceived social support and professional identity.

BACKGROUND: Interprofessional education (IPE) has been advocated for all healthcare students, and readiness for interprofessional learning significantly influences its effectiveness. It is essential to explore the antecedent factors of readiness for interprofessional learning among nursing students to promote IPE. While a proactive personality might impact readiness for interprofessional learning, its specific role has remained unspecified. OBJECTIVE: To examine the mediation effects of perceived social support and professional identity on the association between proactive personality and readiness for interprofessional learning among nursing students. DESIGN: The study utilised a cross-sectional design. SETTINGS: Research was conducted at two universities and two vocational schools in Hainan Province, China. PARTICIPANTS: On-campus nursing students were invited to participate between March and May 2023. METHODS: A flyer was distributed to the participants with a QR code to scan to voluntarily complete the online survey, including the Readiness for Interprofessional Learning Scale (RIPLS), Proactive Personality Scale, Perceived Social Support Scale and Professional Identity Status Questionnaire Scale 5d. Descriptive analysis, Pearson associations and mediation analysis were conducted using SPSS software version 26.0 and PROCESS version 4.2 for SPSS. RESULTS: The participants' average RIPLS score was 66.93 ± 9.28. Proactive personality (r = 0.633, p < 0.01), perceived social support (r = 0.605, p < 0.01) and professional identity (r = 0.549, p < 0.01) were all positively related to readiness for interprofessional learning. Meanwhile, the relationship between proactive personality and readiness for interprofessional learning was partly mediated by perceived social support (25.15 %), professional identity (13.35 %) and the chain effects (9.48 %) of perceived social support and professional identity. CONCLUSIONS: The nursing students in Hainan, China demonstrated a medium level of readiness for interprofessional learning. Compound strategies that foster proactive personality, provide social support and boost positive professional identity are warranted to improve nursing students' readiness for interprofessional learning.

Efficacy of agomelatine with cognitive behavioral therapy for delayed sleep-wake phase disorder in young adults: A randomized controlled study.

BACKGROUND: Delayed sleep-wake phase disorder (DSWPD) is common and easily misdiagnosed in young people, and to date, there is no evidence-based treatment. PURPOSE: A nonblinded randomized controlled study evaluated the effect of agomelatine therapy (AT) and cognitive behavior therapy (CBT) on DSWPD in young adults. METHODS: Sixty adolescents and young adults (range = 19-24 years, mean = 22 years, 52% female) diagnosed with DSWPD were randomized to receive 4 weeks of agomelatine therapy with or without cognitive behavior therapy. Sleep diaries, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Insomnia Severity Index (ISI), and World Health Organization wellbeing questionnaire (WHO-5) were measured pre-treatment and post-treatment. RESULTS: Agomelatine therapy for 4 weeks shifted the sleep-wake rhythm (p < .001) forward in both groups at the week 4 assessment. There were no significant differences in sleep onset (p = .099) and sleep offset (p = .959) between the CBT group and the no treatment (NT) group at the follow-up visits. However, significant differences were found in sleep duration (p = .002), sleep quality (p=0.005), sleep difficulties (p < .001), daytime sleepiness (p = .001), and wellbeing (p = .007) between groups. CONCLUSIONS: The improvements were received largely through the sleep-promoting effects of agomelatine therapy, and combining with cognitive behavior therapy on maintenance of altered sleep rhythms might be feasible.

Long non-coding RNA RPL34-AS1 ameliorates oxygen-glucose deprivation-induced neuronal injury via modulating miR-223-3p/IGF1R axis.

Ribosomal protein L34-antisense RNA 1 (RPL34-AS1), one of the long non-coding RNAs (lncRNAs), plays an important function in regulating diverse human malignant tumors. Nevertheless, the functions of RPL34-AS1 in ischemic stroke remain unclear. The present work focused on determining the candidate targets of RPL34-AS1 and its related mechanism in ischemic injury. The oxygen-glucose deprivation (OGD/R) in vitro cell model and middle cerebral artery occlusion (MCAO) in vivo rat model were utilized to simulate the pathological process of ischemic stroke. Additionally, the CCK8, WB (detecting Bcl-2 and Bax protein levels), and caspase-3 activity assays were done to investigate the anti-apoptotic functions of RPL34-AS1. The relationship among RPL34-AS1, insulin-like growth factor 1 receptor (IGF1R), and microRNA-223-3p (miR-223-3p) was determined through luciferase reporter assay. In this study, RPL34-AS1 expression was reduced in patients suffering from ischemic stroke. The overexpression of RPL34-AS1 reduced ischemic brain damage. However, the cell viability and glucose uptake were increased, and the apoptosis rate was decreased in the OGD/R-induced neurons. Further, miR-223-3p resulted in the decreased cell viability and glucose uptake and the increased cell apoptosis to cause ischemic brain damage. Besides, the neuroprotective effects of RPL34-AS1 on OGD/R injury were partly reversed by miR-223-3p. Mechanistically, lncRNA RPL34-AS1 could function as the competing endogenous RNA (ceRNA) of miR-223-3p to regulate IGF1R. Collectively, our study demonstrated that lncRNA RPL34-AS1 attenuated OGD/R-induced neuronal injury by mediating miR-223-3p/IGF1R axis. This discovery might serve as the candidate therapeutic target for ischemic stroke.

[Mechanisms of Penicillin Wastewater Treatment by Coupled Electrocatalytic and Bioelectrochemical Systems].

Large amounts of wastewater containing residual antibiotics are produced in antibiotics production, but it is difficult for traditional biological wastewater treatment to efficiently treat this high concentration antibiotic wastewater. Coupled electrocatalytic and bioelectrochemical systems were proposed to treat typical ß-lactam antibiotics (penicillin) wastewater. The penicillin wastewater was oxidized by a boron-doped diamond (BDD) electrocatalytic electrode and then steadily treated by a bioelectrochemical system (BES). The penicillin removal rate of the electrocatalytic system was 89%, and 79% of the residual penicillin was further removed by the BES. The maximum power density of the BES with pretreated penicillin of (1124±28) mW·m-2 was increased by 473% compared with that of the BES with raw penicillin. The total penicillin removal rate was 98% in the electrocatalytic and bioelectrochemical system. The results of the BES anode biomass and biofacies showed that Acinetobacter was the dominant bacterial group on the anode before penicillin addition, and it was the main microorganism in the formation of the anode biofilm. Bacillus is an electricity-producing bacterium with a power generation function. Penicillin inhibited the biomass of the mixed anode bacteria and the biological activity of Proteus microorganisms, which were the main electricity-producing bacteria, and reduced the biomass of Acinetobacter and Bacillus. This was the main factor affecting the power generation performance and reactor treatment effect. The pretreatment of penicillin wastewater by electrocatalytic degradation can significantly decrease its concentration, efficiently alleviate the inhibition of the BES by penicillin, and improve the biodegradability of wastewater. The coupled electrocatalytic and bioelectrochemical system is a new technology for antibiotic wastewater treatment with a high efficiency and low energy consumption.

Hemp seed polysaccharides protect intestinal epithelial cells from hydrogen peroxide-induced oxidative stress.

The purpose of this study was to investigate structure of Hemp seed polysaccharide (HSP) and the protective effect of HSP from H2O2-induced oxidative damage in IPEC-1 cells and the possible mechanism of this protection. Analysis of monosaccharide composition and structure of two fractions HSP0 and HSP0.2 from polysaccharide of Hemp seed (HSPc) were analyzed by high performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FT-IR). The results showed that both HSP0 and HSP0.2 contain sulfate groups, which are sulfated polysaccharides. In IPEC-1 cells model, the release of LDH and MDA was significantly decreased, and the activities of SOD, GSH-Px and CAT were significantly increased in HSP0 and HSP0.2-treated group. HSP0.2 dramatically increased the gene expression of antioxidant enzymes and phase II detoxification enzymes measured by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (qRT-PCR). In addition, HSP0.2 up-regulated the expression level of intracellular transcription factor Nuclear factor erythroid-2-related factor 2 (Nrf2) and inhibited the level of Kelch-like ECH-associated protein 1 (Keap1) with Western blot analysis. Collectively, the present study suggested that HSP0.2 has the protective effect of IPEC-1 cells against H2O2-induecd oxidative stress. This protection mechanism may be related to activation of the Keap1/Nrf2 signaling pathway.

Immunomodulatory effect of low molecular-weight seleno-aminopolysaccharide on immunosuppressive mice.

Low molecular-weight seleno-aminopolysaccharides (LSA) have been shown to possess a variety of biological activities in vitro. In the present study, we further investigated the immunomodulatory effect of LSA on immunosuppressive mice induced by cyclophosphamide (CPA) and its molecular mechanism. The results demonstrated that LSA could significantly increase spleen and thymus indices, proliferation of splenic lymphocyte, the secretion of cytokines (IL-2, IL-4, IL-10 and INF-γ) of serum and ileum, and secretory immunoglobulin A (sIgA) content of small intestine. LSA dramatically improved the gene expression levels of IL-2, IL-4, IL-10 and INF-γ in small intestine by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Furthermore, our data indicated that LSA could significantly increase the gene expression levels of IL-1ß and iNOS in RAW264.7 cells. LSA was further shown to remarkably promote inhibitor kappa Bα (IκBα) and nuclear factor-kappa B (NF-κB) p65 phosphorylation with western blot analysis. Taken together, these findings suggest that LSA has immunomodulatory activity on immunosuppressive mice and macrophage RAW264.7 cells, and its mechanism may be related to activation of NF-κB signaling pathway.

Facile Preparation of Metal-Organic Framework (MIL-125)/Chitosan Beads for Adsorption of Pb(II) from Aqueous Solutions.

In this study, novel composite titanium-based metal-organic framework (MOF) beads were synthesized from titanium based metal organic framework MIL-125 and chitosan (CS) and used to remove Pb(II) from wastewater. The MIL-125-CS beads were prepared by combining the titanium-based MIL-125 MOF and chitosan using a template-free solvothermal approach under ambient conditions. The surface and elemental properties of these beads were analyzed using scanning electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopies, as well as thermal gravimetric analysis. Moreover, a series of experiments designed to determine the influences of factors such as initial Pb(II) concentration, pH, reaction time and adsorption temperature was conducted. Notably, it was found that the adsorption of Pb(II) onto the MIL-125-CS beads reached equilibrium in 180 min to a level of 407.50 mg/g at ambient temperature. In addition, kinetic and equilibrium experiments provided data that were fit to the Langmuir isotherm model and pseudo-second-order kinetics. Furthermore, reusability tests showed that MIL-125-CS retained 85% of its Pb(II)-removal capacity after five reuse cycles. All in all, we believe that the developed MIL-125-CS beads are a promising adsorbent material for the remediation of environmental water polluted by heavy metal ions.

Protective effect of low molecular-weight seleno-aminopolysaccharides against H2O2-induecd oxidative stress in intestinal epithelial cells.

Organoselemium compounds possess strong antioxidant activity as well as protecting cells from DNA damage, mitochondrial injury, lipid peroxidation, protein denaturation and cell death. Herein, we used an in vitro oxidative model to further investigate the antioxidant effects of a novel organoselemium compound, low molecular-weight seleno-aminopolysaccharides (LSA) in intestinal porcine epithelial cells (IPEC-1), and the molecular mechanisms of these effects. Analysis by MTT assay showed that LSA could significantly increase the viability of IPEC-1 cells compared to cells exposed to H2O2. We found that the levels of different antioxidant enzymes could dramatically increase in LSA pretreatment group compared to H2O2 treatment group. Furthermore, LSA significantly increased the gene expression of antioxidant enzymes and phase 2 detoxifying enzymes in IPEC-1 cells, as measured by qRT-PCR. In addition, LSA up-regulated the expression level of intracellular transcription factor NF-E2-related factor 2 (Nrf2) and inhibited the level of kelch-like ECH-associated protein 1 (Keap1) with western blot analysis. Collectively, the present study suggested that LSA has the protective effect of IPEC-1 cells against H2O2-induecd oxidative stress, and its mechanism may be related to activation of Keap1/Nrf2 signaling pathway in intestinal epithelial cells.

Risk factors and the preoperative assessment of right para-oesophageal lymph node metastasis in right lobe papillary thyroid carcinoma: A case series.

BACKGROUND: Right para-oesophageal lymph nodes (RPELN) are included among the right central compartment lymph nodes (rCLN) and located behind right recurrent laryngeal nerve (rRLN). However, due to the likelihood of increasing postoperative complications, and the extremely difficulties of RPELN dissection, the decision to perform RPELN dissection remains controversial. The aim of this study was to explore the risk factors of RPELN metastasis and evaluate RPELN metastasis by preoperative examination. METHODS: We reviewed the medical records of 163 consecutive papillary thyroid carcinoma (PTC) patients (125 females and 38 males) who underwent right lobe plus isthmic resection (91 patients) or total thyroidectomy (72 patients) with right or bilateral central compartment lymph node dissection. The RPELN dissections were performed in all patients and were individually dissected and recorded intraoperatively. All patients underwent thyroid ultrasound and enhanced neck computed tomography (CT) routinely during preoperative examination. RESULTS: RPELN metastasis was detected in 20 patients (12.3%), among whom 6 (3.7%) had RPELN metastasis without rCLN metastasis. Total rCLN metastasis and lateral compartment lymph node metastasis were confirmed in 57 (35.0%) and 24 (14.7%) patients, respectively. The tumour diameter, number of metastatic rCLN and lateral compartment lymph nodes, RPELN visible on CT, and enhanced CT value of RPELN were confirmed significantly associated with RPELN metastasis by univariate analysis (P < 0.05). The area under the ROC curve of CT values was 0.77 (95% CI, 0.59-0.95; P = 0.003). The CT value of 132.0 was used as the cut-off point, and the specificity and sensitivity were 84.1% and 71.4%, respectively. CONCLUSIONS: PTC patients with a large tumour (>1 cm) in the right lobe or suspected rCLN metastasis were recommended to undergo prophylactic RPELN dissection, particularly in those with a high enhanced CT value (>132) of RPELN or those with the copresence of lateral compartment lymph node metastasis.

The 15-LO-1/15-HETE system promotes angiogenesis by upregulating VEGF in ischemic brains.

OBJECTIVES: Angiogenesis promotes neurobehavioral recovery after cerebral ischemic stroke. 15(S)-hydroxyeicosatetraenoic acid (15-HETE) is one of the major metabolites of arachidonic acid by 15-lipoxygenase (15-LO) and stimulates the production of vascular endothelial growth factor (VEGF), thus, inducing autocrine-mediated angiogenesis. The present study aimed to investigate the role of 15-LO/15-HETE system on VEGF expression and angiogenesis in brain ischemia. METHODS: Rat cerebral arterial vascular endothelial cells were used to set up a cell injury model of oxygen-glucose deprivation and reoxygenation (OGD/R), mimicking a condition of brain ischemia. A mouse model of middle cerebral artery occlusion (MCAO) was established. RESULTS: Oxygen-glucose deprivation increased cellular expression of 15-LO-1 and VEGF. Transfection of 15-LO-1 siRNA depleted cells of 15-LO-1, and sequentially induced downregulation of VEGF expression; while, incubation of 15-HETE increased the expression of VEGF. Incubation of 15-HETE attenuated the reduction in cell viability induced by oxygen-glucose deprivation, and promoted cell migration, while transfection of 15-LO-1 siRNA showed an opposite effect. In animal experiments, the density of microvessels in hypoxic regions of brains was significantly increased after MCAO, while intracerebroventricular delivery of 15-LO-1 siRNA significantly reduced the density of microvessels, and downregulates VEGF expression. DISCUSSION: The results indicate that the 15-LO-1/15-HETE system promotes angiogenesis in ischemic brains by upregulation of VEGF, representing a potential target for improving neurobehavioral recovery after cerebral ischemic stroke.

Immunomodulatory effect of low molecular-weight seleno-aminopolysaccharides in intestinal epithelial cells.

Seleno-polysaccharides possess a variety of biological activities. In the present study, we further investigated the immunomodulatory effects of low molecular-weight seleno-aminopolysaccharides (LSA) in intestinal porcine epithelial cells (IPEC-1), and the molecular mechanisms of these effects. Analysis by ELISAs revealed that LSA could significantly increase the secretion of nitric oxide (NO), interleukin- 6 (IL-6), interleukin- 10 (IL-10), and tumor necrosis factor alpha (TNF-α). Moreover, LSA dramatically increased the gene expression levels of TNF-α, IL-6, IL-10, and iNOS in IPEC-1 cells, as determined by qRT-PCR. Western blot analysis further determined that LSA promotes inhibitor kappa B α (IĸBα), nuclear factor- kappa B (NF-κB) p65 phosphorylation. Taken together, these findings suggested that LSA has immunomodulatory activity on IPEC-1 cells, and its mechanism may be related to activation of the NF-ĸB signaling pathway.

Molecular Weight-Dependent Immunostimulative Activity of Low Molecular Weight Chitosan via Regulating NF-κB and AP-1 Signaling Pathways in RAW264.7 Macrophages.

Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been found to possess many important biological properties, such as antioxidant and antitumor effects. In our previous study, LMWCs were found to elicit a strong immunomodulatory response in macrophages dependent on molecular weight. Herein we further investigated the molecular weight-dependent immunostimulative activity of LMWCs and elucidated its mechanism of action on RAW264.7 macrophages. LMWCs (3 kDa and 50 kDa of molecular weight) could significantly enhance the mRNA expression levels of COX-2, IL-10 and MCP-1 in a molecular weight and concentration-dependent manner. The results suggested that LMWCs elicited a significant immunomodulatory response, which was dependent on the dose and the molecular weight. Regarding the possible molecular mechanism of action, LMWCs promoted the expression of the genes of key molecules in NF-κB and AP-1 pathways, including IKKß, TRAF6 and JNK1, and induced the phosphorylation of protein IKBα in RAW264.7 macrophage. Moreover, LMWCs increased nuclear translocation of p65 and activation of activator protein-1 (AP-1, C-Jun and C-Fos) in a molecular weight-dependent manner. Taken together, our findings suggested that LMWCs exert immunostimulative activity via activation of NF-κB and AP-1 pathways in RAW264.7 macrophages in a molecular weight-dependent manner and that 3 kDa LMWC shows great potential as a novel agent for the treatment of immune suppression diseases and in future vaccines.

Composition and anti-inflammatory effect of polysaccharides from Sargassum horneri in RAW264.7 macrophages.

Sulfated polysaccharides extracted from brown marine algae have been shown to possess a variety of biological activities. We assessed the potential activity of the sulfated polysaccharide from Sargassum horneri (SP) and its isolated two major components (fraction-1 (F1) and fraction-2 (F2)), on anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. In the present study, analysis of polysaccharide chemical composition found that the constituent ratios of sulfate ester and fucose in SP and F1 were 4.95% vs 7.6%, and 4.48% vs 55.9%, respectively, suggesting that F1 may be a major sulfated polysaccharide containing fucose. Meanwhile, our findings demonstrated that TNF-α secretion levels were significantly (P<0.05) decreased by SP and F1 treatments in LPS-stimulated RAW264.7 cells in a dose-dependent manner under the preventive and repair experimental models. Pro-/anti-inflammatory (TNF-α/IL-10) cytokines secretion ratios by LPS-stimulated RAW264.7 macrophages were significantly (P<0.05) inhibited by SP and F1 treatments, particularly by F1 (at high dose, 200µg/ml). Moreover, NO release and iNOS activity were significantly (P<0.05) inhibited by F1. Collectively, the present study suggested that purified component, F1 from SP, had strong anti-inflammatory effects on LPS-stimulated RAW264.7 macrophages in the preventive and repair manner through inhibiting TNF-α secretion levels and NO release.

Fucosterol, a sterol extracted from Sargassum fusiforme, shows antidepressant and anticonvulsant effects.

We previously showed that extracts of Sargassum fusiforme significantly reduce immobility time in the forced swim test and tail suspension test, suggesting that these extracts possess antidepressant-like effects. Here, fucosterol extracted from S. fusiforme was evaluated for antidepressant and anticonvulsant activities in mice. Fucosterol (10, 20, 30 and 40mg/kg) significantly shortened immobility time in the forced swim test and tail suspension test for30min after treatment but had no effect on locomotor activity in the open field test. Fucosterol significantly increased serotonin, norepinephrine and the metabolite 5-hydroxyindoleacetic acid in mouse brain, suggesting that the effects of fucosterol may be mediated through these neurotransmitters. As assessed using maximal electroshock, fucosterol (20, 40, 100mg/kg) possessed anticonvulsant activity, whereas rotarod toxicity test results indicated that fucosterol did not induce neurotoxicity at the same dose levels in mice. Thus, fucosterol may be a useful antidepressant adjunct candidate for treating depression in patients with epilepsy. A significant increase in hippocampal brain-derived neurotrophic factor (BDNF) levels was found in the fucosterol 20mg/kg group (P<0.05). Our findings suggested that fucosterol may possess an antidepressant-like effect, which may be mediated by increasing central BDNF levels.

Immunostimulative Activity of Low Molecular Weight Chitosans in RAW264.7 Macrophages.

Chitosan and its derivatives such as low molecular weight chitosans (LMWCs) have been reported to exert many biological activities, such as antioxidant and antitumor effects. However, complex and molecular weight dependent effects of chitosan remain controversial and the mechanisms that mediate these complex effects are still poorly defined. This study was carried out to investigate the immunostimulative effect of different molecular weight chitosan in RAW264.7 macrophages. Our data suggested that two LMWCs (molecular weight of 3 kDa and 50 kDa) both possessed immunostimulative activity, which was dependent on dose and, at the higher doses, also on the molecular weight. LMWCs could significantly enhance the the pinocytic activity, and induce the production of tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), interferon-γ (IFN-γ), nitric oxide (NO) and inducible nitric oxide synthase (iNOS) in a molecular weight and concentration-dependent manner. LMWCs were further showed to promote the expression of the genes including iNOS, TNF-α. Taken together, our findings suggested that LMWCs elicited significantly immunomodulatory response through up-regulating mRNA expression of proinflammatory cytokines and activated RAW264.7 macrophage in a molecular weight- and concentration-dependent manner.

The protective effect of epoxyeicosatrienoic acids on cerebral ischemia/reperfusion injury is associated with PI3K/Akt pathway and ATP-sensitive potassium channels.

Epoxyeicosatrienoic acids (EETs), the cytochrome P450 epoxygenase metabolite of arachidonic acid, have been demonstrated to have neuroprotective effect. Phosphatidylinositol 3-kinase (PI3K)/Akt and ATP-sensitive potassium (KATP) channels are thought to be important factors that mediate neuroprotection. However, little is known about the role of PI3K/Akt and KATP channels in brain after EETs administration. In vitro experiment, oxygen-glucose deprivation (OGD) was performed in cultured rat cerebral microvascular smooth muscle cells (SMCs) for 4 h. The effect of 14,15-EET on OGD induced cell apoptosis was examined after reoxygenation. Western blot and real-time PCR were used to analyze the expression of Kir6.1, SUR2B (two subunits of KATP channels) and p-Akt on cerebral microvascular SMCs. In vivo experiments, we use 12-(3-adamantan-1-yl-ureido)-dodecanoic acid [AUDA, a specific soluble epoxide hydrolase (sEH) inhibitor] to confirm the effect of EETs indirectly. Rats were injected intraperitoneally with AUDA before being subjected to middle cerebral artery occlusion (MCAO). We detected the apoptosis and the expression of p-Akt, Kir6.1 and SUR2B in ischemic penumbra. The results showed that EETs protect against cerebral ischemia/reperfusion (I/R) injury and upregulated the expression of p-Akt and Kir6.1 in both of ischemic penumbra and OGD induced cerebral microvascular SMCs. The protective effect was inhibited by Wortmannin (a specific PI3K inhibitor) and Glib (a specific KATP inhibitor) respectively in vitro experiment. In conclusion, these results suggested that the protective effect of EETs on cerebral I/R injury is associated with PI3K/Akt pathway and KATP channels. Furthermore, the PI3K pathway may contribute to mediating KATP channels on cerebral microvascular SMCs.

Protective effect of polysaccharides from Sargassum horneri against oxidative stress in RAW264.7 cells.

This study was designed to investigate chemical composition and the protective effects of polysaccharides isolated from Sargassum horneri against hydrogen peroxide (H2O2)-induced oxidative injury in RAW264.7 cells. Results showed that isolated polysaccharides (SHSc) and the major fractions (SHS1, SHS0.5) contained sulfate ester, and SHS1 was high fucose-containing sulfated polysaccharide. After preincubation with three isolated polysaccharides, RAW264.7 cells viability were significantly restored and decreased in cellular LDH release (P<0.05). SHS1 and SHS0.5 decreased intracellular ROS level, intracellular NO and malonic dialdehyde (MDA) level (P<0.05), restoring activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) (P<0.05), decreasing inducible nitric oxide synthase (iNOS) (P<0.05). Moreover, preincubation of SHS1 with RAW264.7 cells resulted in the increase of the gene expression level of endogenous antioxidant enzymes such as MnSOD and GSH-Px (P<0.05). These results clearly showed that SHSc and its fractions could attenuate H2O2-induced stress injury in RAW264.7 cells, and a similar efficiency in protecting RAW264.7 cells against H2O2-induced oxidative injury between SHS1 and Vitamin C. Taken together, our findings suggested that SHS1 can effectively protect RAW264.7 cells against oxidative stress by H2O2, which might be used as a potential natural antioxidant in the functional food and pharmaceutical industries.

Chitosan nanoparticles attenuate hydrogen peroxide-induced stress injury in mouse macrophage RAW264.7 cells.

This study was carried out to investigate the protective effects of chitosan nanoparticles (CNP) against hydrogen peroxide (H2O2)-induced oxidative damage in murine macrophages RAW264.7 cells. After 24 h pre-incubation with CNP (25-200 µg/mL) and chitosan (CS) (50-200 µg/mL, as controls), the viability loss in RAW264.7 cells induced by H2O2 (500 µM) for 12 h was markedly restored in a concentration-dependent manner as measured by MTT assay (P < 0.05) and decreased in cellular LDH release (P < 0.05). Moreover, CNP also exerted preventive effects on suppressing the production of lipid peroxidation such as malondialdehyde (MDA) (P < 0.05), restoring activities of endogenous antioxidant including superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) (P < 0.05), along with increasing total antioxidant capacity (T-AOC) (P < 0.05). In addition, pre-incubation of CNP with RAW264.7 cells for 24 h resulted in the increase of the gene expression level of endogenous antioxidant enzymes, such as MnSOD and GSH-Px (P < 0.05). At the same concentration, CNP significantly decreased LDH release and MDA (P < 0.05) as well as increased MnSOD, GSH-Px, and T-AOC activities (P < 0.05) as compared to CS. Taken together, our findings suggest that CNP can more effectively protect RAW264.7 cells against oxidative stress by H2O2 as compared to CS, which might be used as a potential natural compound-based antioxidant in the functional food and pharmaceutical industries.

Astragaloside IV reduces cerebral edema post-ischemia/reperfusion correlating the suppression of MMP-9 and AQP4.

Cerebral edema is a critical complication after intravascular thrombolysis post-acute stroke. However, clinical options remained limited for treating cerebral edema after cerebral ischemia/reperfusion (I/R) injury. In the present study, astragaloside IV, a purified extract from astragalus membranaceus, was used in the focal I/R rat model, aimed to investigate its effect on the cerebral edema. We found that astragaloside IV (10 and 20mg/kg) significantly attenuated the cerebral water content (P<0.05) and improved neurological outcomes (P<0.05) in comparison with vehicle group. Moreover, we investigate the effect of astragaloside IV on the (blood-brain barrier) BBB since cerebral edema was closely related to the permeability of the BBB. We found that the permeability of BBB was improved significantly in astragaloside IV groups compared with vehicle group via Evans blue leakage (P<0.05). This was further confirmed under the electron microscope, using lanthanum as a tracer of blood vessel permeability. Lanthanum was usually found within the blood vessel in sham group, rather than in perivascular tissues as shown in vehicle group. In drug groups, lanthanum stain was mainly restricted within the cerebral capillary, indicating the potential BBB-protective effect of astragaloside IV. Furthermore, we found that expressions of Matrix metalloproteinase-9 (MMP-9) and aquaporin 4 (AQP4) were increased in vehicle group, which were related to cerebral vasogenic edema or cytotoxic edema. The up-regulations of MMP-9 and AQP4 were inhibited significantly by astragaloside IV administration. We propose that the anti-edema potential of astragaloside IV was correlated with its regulation of MMP-9 and AQP4.