Preparation of Microcrystalline Cellulose/N-(2-aminoethyl)-3- Aminopropyl Methyl Dimethoxysilane Composite Aerogel and Adsorption Properties for Formaldehyde.

Air pollution is related to the development of the national economy and people's livelihoods. Formaldehyde, as one of the main pollutants in the air, affects people's physical and mental health. In order to remove formaldehyde and better protect the health of residents, it is necessary to develop efficient adsorption materials. In this study, APMDS-modified cellulose composite aerogel microcrystalline was investigated. The adsorption of formaldehyde by the MCC/APMDS (Microcrystalline Cellulose/N-(2-aminoethyl)-3- Aminopropyl Methyl Dimethoxysilane) composite aerogel mainly relied upon the reaction of the protonated -NH3+ group in APMDS with formaldehyde to form a Schiff base to achieve the effect of deformaldehyde. Meanwhile, the modification of the aerogel reduced the pore volume and specific surface area, and the average pore size increased to 14.56 nm, which enhanced the adsorption capacity of formaldehyde, and the adsorption amount reached 9.52 mg/g. This study provides valuable information for the preparation of adsorbent materials with high formaldehyde adsorption capacity for air purification.

Biomass-Based Polymer Nanoparticles With Aggregation-Induced Fluorescence Emission for Cell Imaging and Detection of Fe3+ Ions.

Polymeric nanoparticles, which show aggregation-induced luminescence emission, have been successfully prepared from larch bark, a natural renewable biomass resource, in a simple, rapid ultrasonic fragmentation method. The structure, element, particle size and molecular weight distribution of larch bark extracts (LBE) were studied by FTIR, XPS, TEM, XRD and linear mode mass spectrometry, respectively. LBE was found containing large numbers of aromatic rings, displaying an average particle size of about 4.5 nm and mainly presenting tetramers proanthocyanidins. High concentration, poor solvent, low temperature and high viscosity restricted the rotation and vibration of the aromatic rings in LBE, leading to the formation of J-aggregates and enhancing the aggregation-induced fluorescence emission. LBE possessed good resistance to photobleaching under ultraviolet light (200 mW/m2). Cytotoxicity experiments for 24 h and flow cytometry experiments for 3 days proved that even the concentrations of LBE as high as 1 mg/mL displayed non-toxic to MG-63 cells. Therefore, LBE could be employed for MG-63 cell imaging, with similar nuclear staining to the DAPI. The effects of different metal ions on the fluorescence emission intensity of LBE were analyzed and exhibited that Fe3+ owned obvious fluorescence quenching effect on LBE, while other metal ions possessed little or weak effect. Furthermore, the limit of detection (LOD) of Fe3+ was evaluated as 0.17 µM.

Structural characterization and α-glycosidase inhibitory activity of a novel polysaccharide fraction from Aconitum coreanum.

α-Glycosidase is an essential target for the management of postprandial serum glucose in diabetic patients. Therefore, the interest has been growing in the screening of α-glycosidase inhibitor from natural resource. In the present study, the structure and α-glycosidase inhibitory activity of a polysaccharide (named as ACPP-1) from Aconitum coreanum were investigated. Based on the results from high performance gel permeation chromatography, GC-MS and 1D/2D nuclear magnetic resonance spectroscopy, ACPP-1 was a highly-linear polysaccharide with a molecular weight of 34.0 kD and containing over 90 % of glucose. It was composed of (1→4)-α-d-Glcp and α-Araf. ACPP-1 exhibited a dose-dependent inhibitory eff ;ect against α-glycosidase activity in vitro and the IC50 value was ∼0.8 mg/mL. In oral starch tolerance test, treatment with ACPP-1 (800 mg/kg) significantly improved the starch tolerance in mice. Taken together, this study provided a potential intervention and management for postprandial hyperglycemia by the polysaccharide fraction from A. coreanum.

Sulfated polysaccharides from Rhodiola sachalinensis reduce d-gal-induced oxidative stress in NIH 3T3 cells.

In this study, three sulfated polysaccharides (S-RSP1-2, S-RSP1-4 and S-RSP1-8) from Rhodiola sachalinensis were produced by chlorosulfonic acid-pyridine method. d-gal was used to develop an oxidative stress model in the mouse embryonic fibroblast cell line NIH 3T3. Effects of the three sulfated polysaccharides on d-gal-induced oxidative stress were investigated. The results showed that S-RSP1-4 improved the viability of the d-gal-induced oxidative stress in NIH 3T3 cells. The sulfated polysaccharides were found to have a better protective effect against d-gal-induced oxidative stress as compared to the native polysaccharide. Scanning electronmicroscopy also showed a significant change in the surface morphology of sulfated polysaccharides. In addition, the sulfated polysaccharides had noticeable DPPH radical-scavenging activity. In summary, our results demonstrated that d-gal was able to induce oxidative stress in NIH 3T3 cells, and sulfated group might play an important role in resistance to d-gal-induced oxidative damage.

c-Abl tyrosine kinase regulates neutrophil crawling behavior under fluid shear stress via Rac/PAK/LIMK/cofilin signaling axis.

The excessive recruitment and improper activation of polymorphonuclear neutrophils (PMNs) often induces serious injury of host tissues, leading to inflammatory disorders. Therefore, to understand the molecular mechanism on neutrophil recruitment possesses essential pathological and physiological importance. In this study, we found that physiological shear stress induces c-Abl kinase activation in neutrophils, and c-Abl kinase inhibitor impaired neutrophil crawling behavior on ICAM-1. We further identified Vav1 was a downstream effector phosphorylated at Y174 and Y267. Once activated, c-Abl kinase regulated the activity of Vav1, which further affected Rac1/PAK1/LIMK1/cofilin signaling pathway. Here, we demonstrate a novel signaling function and critical role of c-Abl kinase during neutrophil crawling under physiological shear by regulating Vav1. These findings provide a promising treatment strategy for inflammation-related disease by inactivation of c-Abl kinase to restrict neutrophil recruitment.

Bupleurum chinense polysaccharide inhibit adhesion of human melanoma cells via blocking ß1 integrin function.

Adhesive interaction contributes toward tumor metastasis and the transmembrane glycoprotein receptor, integrin has been recognized to mediate the adhesion to extracellular matrix thus upregulating tumor metastasis. In the current study, we evaluated the anti-adhesive mechanisms of a water-soluble polysaccharide (BCP) extracted from Bupleurum chinense. BCP inhibited integrin-mediated adhesion of human melanoma A375 cells to fibronectin but had no effects on nonspecific adhesion to poly-l-lysine. BCP also reduced ß1 integrin ligand affinity for GST-FNIII9-10 proteins. The adhesion-dependent formation of F-actin stress fiber and focal adhesion (FA) was also inhibited by BCP treatment. The inhibition of BCP on integrin-mediated signaling is probably through inhibiting phosphorylation of focal adhesion kinase (FAK) and paxillin. Collectively, our current findings indicated that BCP may be a potential therapy for melanoma metastasis due to its inhibitory effects on integrin function.

Characterization of a polysaccharide from Rosa davurica and inhibitory activity against neutrophil migration.

The rapid recruitment of neutrophils from peripheral blood into infected sites is critical step for inflammatory responses; however, the excessive and improper recruitment can lead to serious tissue damages. Thus, it is a promising strategy to inhibit their excessive recruitment for treating inflammation-related disease. Here, we isolated a polysaccharide (RDPA1) from Rosa davurica, to evaluate its physicochemical property and inhibitory effects on neutrophil migration. RDPA1 was obtained by hot-water extraction, ethanol precipitation, and fractionated by DEAE-cellulose and Sepharose CL-6B columns. RDPA1 significantly inhibited in vitro migration of human neutrophils evaluated by transwell chamber and impacted the migratory behavior observed by time-lapsed microscopy, we found the migrated distance and average velocity of RDPA1-treated cells were greatly reduced. In addition, RDPA1 treatment impaired in vivo neutrophil infiltration in the peritonitis mice. RDPA1 exhibited significant blocking capacity of the interaction between ß2 integrins and ICAM-1 evaluated by flow cytometry and in vitro protein binding assay. Together, these results suggest RDPA1 could be considered as a potential candidate for developing a novel anti-inflammatory agent.

Macrophage activation induced by the polysaccharides isolated from the roots of Sanguisorba officinalis.

CONTEXT: Macrophage, involved at all stages of immune response, is an important component of the host defense system. Polysaccharides exist almost ubiquitously in medical plants and most of them possess immunomodulation and macrophage activation properties. OBJECTIVE: This study elucidates the effects on macrophage activation and molecular mechanism induced by the polysaccharides (SOPs) from the roots of Sanguisorba officinalis Linne (Rosaceae). MATERIALS AND METHODS: Polysaccharides (SOPs) from the roots of S. officinalis were obtained by water extraction and ethanol precipitation. Physicochemical characterization of SOPs was analyzed by phenol-sulfuric acid, m-hydroxydiphenyl, Bradford method, and gas chromatography. Phagocytic capacity of RAW 264.7 macrophages incubated with SOPs (25 and 100 µg/ml) was determined by the aseptic neutral red method. Macrophages were incubated with SOPs (25 and 100 µg/ml), and the TNF-α and NO the secretion were measured using ELISA kit and Griess reagent, respectively. In addition, TNF-α and iNOS transcripts were evaluated by semi-quantitative RT-PCR, and NF-κB signaling activation was detected by Western blot assay. RESULTS: SOPs enhanced the phagocytosis capacity of macrophages to aseptic neutral red solution and increased TNF-α and NO secretion. The amounts of TNF-α and iNOS transcript were increased significantly at the mRNA level when macrophages were exposed to SOPs. Meanwhile, the stimulation of macrophages by SOPs induced phosphorylation of p65 at serine 536 and a marked decrease of IκB expression. DISCUSSION AND CONCLUSION: These results suggested that SOPs exhibited significant macrophage activation properties through NF-κB signaling pathway and could be considered as a new immunopotentiator.

Inhibitory function of P-selectin-mediated leukocyte adhesion by the polysaccharides from Sanguisorba officinalis.

CONTEXT: P-selectin is a promising target for inflammatory-related diseases. Polysaccharides are the active ingredients of Sanguisorba officinalis L. (Rosaceae) responsible for its anti-inflammatory activities; however, the molecular mechanism is not clear yet. OBJECTIVE: This study evaluates the effects of polysaccharides (SOPs) from Sanguisorba officinalis on their antagonistic function against P-selectin-mediated leukocyte adhesion. MATERIALS AND METHODS: The antagonistic function of SOPs was investigated by flow cytometry and static adhesion assay at the concentrations of 25 and 100 µg/ml. The dynamic interaction between HL-60 cells and CHO-P cell monolayer treated with SOPs (25 and 100 µg/ml) was analyzed in a parallel plate flow chamber, and quantitatively calculated by ImageJ software (NIH, Bethesda, MD). In vitro protein binding assay was carried out to evaluate the blocking effects of SOPs (25 and 100 µg/ml) on the interaction between P-selectin and PSGL-1. RESULTS: SOPs-treatment (100 µg/ml) significantly reduced the percentage of HL-60 cells binding to P-selectin (p < 0.01) determined by flow cytometry. In addition, SOPs (25 and 100 µg/ml) markedly blocked the adhesion between HL-60 cells and CHO-P cells under static condition, and the inhibitory rates reached 39.9% and 71.2%, respectively. Compared with the positive control group, SOPs-treatment (25 and 100 µg/ml) significantly reduced the percentage of HL-60 cells rolling on CHO-P cell monolayers by 43.5% and 75.2%, respectively. Protein binding assay showed the interaction between P-selectin and PSGL-1 was significantly blocked by SOPs. DISCUSSION AND CONCLUSION: SOPs possess a significant antagonistic function against P-selectin-mediated leukocyte adhesion, and SOPs could be considered as a promising candidate for amelioration of inflammation-related diseases.

Inhibition of inflammatory injure by polysaccharides from Bupleurum chinense through antagonizing P-selectin.

P-selectin-mediated adhesion between endothelium and neutrophils is a crucial process leading to acute inflammatory injure. Thus, P-selectin has been considered as promising target for therapeutics of acute inflammatory-related diseases. In the present study, the water-soluble polysaccharides (BCPs) were isolated from Bupleurum chinense, and we evaluated their therapeutical effects on acute inflammatory injure and antagonistic function against P-selectin-mediated neutrophil adhesion. Our results showed that BCPs significantly impaired the leukocyte infiltration and relieve lung injury in LPS-induced acute pneumonia model. BCPs significantly blocked the binding of P-selectin to neutrophils and inhibited P-selectin-mediated neutrophils rolling along CHO-P cell monolayer. The result from in vitro protein binding assay showed a direct evidence indicating that BCPs-treatment significantly eliminated the interaction between rhP-Fc and its physiological ligand PSGL-1 at protein level. Together, these results provide a novel therapeutical strategy for amelioration of inflammation-related disease processes by polysaccharides from B. chinense.

Two new proanthocyanidins from the leaves of Garcinia multiflora.

Two new proanthocyanidins, namely garcinianin A (1) and garcinianin B (2), together with two known compounds (3 and 4) were isolated from the leaves of Garcinia multiflora Champ. Their structures were elucidated on the basis of spectroscopic analysis.