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1.
Small ; 20(4): e2304393, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37712098

ABSTRACT

Healed defects on photocatalysts surface and their interaction with plasmonic nanoparticles (NPs) have attracted attention in H2 production process. In this study, surface oxygen vacancy (Vo ) defects are created on ZnO (Vo -ZnO) NPs by directly pyrolyzing zeolitic imidazolate framework. The surface defects on Vo -ZnO provide active sites for the diffusion of single Au atoms and as nucleation sites for the formation of Au NPs by the in situ photodeposition process. The electronically healed surface defects by single Au atoms help in the formation of a heterojunction between the ZnO and plasmonic Au NPs. The formed Au/Vo -Au:ZnO-4 heterojunction prolongs photoelectron lifetimes and increases donor charge density. Therefore, the optimized photocatalysts of Au/Vo -Au:ZnO-4 has 21.28 times higher H2 production rate than the pristine Vo -ZnO under UV-visible light in 0.35 m Na2 SO4 and 0.25 m Na2 SO3 . However in 0.35 m Na2 S and 0.25 m Na2 SO3 , the H2 production rate is 25.84 mmole h-1 g-1 . Furthermore, Au/Vo -Au:ZnO-4 shows visible light activity by generating hot carries via induced surface plasmonic effects. It has 48.58 times higher H2 production rate than pristine Vo -ZnO. Therefore, this study infers new insight for defect healing mediated preparation of Au/Vo -Au:ZnO heterojunction for efficient photocatalytic H2 production.

2.
ACS Appl Mater Interfaces ; 15(18): 21974-21981, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37000640

ABSTRACT

To develop a highly efficient solar cell using organometal halide perovskites, its microscale structure control is one of the most important factors because the microstructural defects inside the organometal halide perovskite are harmful to charge carrier flow and, thus, degrade device performance. In this study, we confirmed the existence of large physical gaps at the grain boundary in a methylammonium iodide (MAPbI3, MA = CH3NH3) perovskite with transmission electron microscopy (TEM) analysis and revealed that the physical gap prevents charge carrier flow in the MAPbI3 perovskite. To minimize the physical gap and its negative influences, the grain size of the MAPbI3 perovskite was optimized by increasing the portion of the cubic phase via microstructural phase control using liquid nitrogen (LN2). Through microstructural phase control of the MAPbI3 perovskite, its grain boundaries and physical gap were significantly decreased, and 20.23% power conversion efficiency (PCE) was achieved with a single cation MAPbI3 perovskite solar cell.

3.
Adv Mater ; 33(40): e2101574, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34402119

ABSTRACT

In response to the Comment on article "Self-Organized Superlattice and Phase Coexistence inside Thin Film Organometal Halide Perovskite", it is suggested that the facts that the existence of hexagonal PbI2 is discrepant in 3D crystallographic interpretation and that observation of ( 0 1 ¯ 0 ) and (100) reflections occurs in general, together make the challenges that were raised in the published Comment less convincing. In addition, a new transmission electron microscopy method using direction-selective electron beam damage of the organometal halide perovskite is disclosed.

4.
ACS Appl Mater Interfaces ; 11(15): 14222-14228, 2019 Apr 17.
Article in English | MEDLINE | ID: mdl-30912424

ABSTRACT

Stretchable alternating-current electroluminescent (ACEL) devices are required due to their potential in wearable, biomedical, e-skin, robotic, lighting, and display applications; however, one of the main hurdles is to achieve uniform electroluminescence with an optimal combination of transparency, conductivity, and stretchability in electrodes. We therefore propose a fabrication scheme involving strategically combining two-dimensional graphene layers with a silver nanowire (Ag NW)-embedded PEDOT:PSS film. The developed hybrid electrode overcomes the limitations of commonly known metallic NWs and ionic conductor-based electrodes for ACEL applications. Furthermore, the potential of the hybrid electrode is realized in demonstrating large-area stretchable ACEL devices composed of an 8 × 8 passive array. The prototype ACEL passive array demonstrates efficient and uniform electroluminescence under high levels of mechanical deformation such as bending, rolling, twisting, and stretching.

5.
ACS Appl Mater Interfaces ; 10(31): 26293-26302, 2018 Aug 08.
Article in English | MEDLINE | ID: mdl-30016061

ABSTRACT

Dual-source vapor-phase deposition enables low-temperature fabrication of high-performance planar structure perovskite (CH3NH3PbI3) solar cells (PSCs), applicable in tandem devices or for industrial production with high homogeneity. Herein, we report low-temperature fabrication of high-efficiency PSCs by dual-source vapor-phase deposition and significance of TiO2 surface modification with [6,6]-phenyl C61 butyric acid methyl ester (PCBM) on cell performance. Co-evaporation of PbI2 and CH3NH3I, as confirmed by X-ray diffraction and high-resolution transmission electron microscopy analyses, results in CH3NH3PbI3 layers with a well-crystallized tetragonal phase formed on both TiO2 and TiO2/PCBM electron-transport layers (ETLs). The devices with PCBM interlayer between TiO2 and CH3NH3PbI3 showed remarkably higher performance than those with TiO2 only, which was attributed to enhance charge extraction and reduced recombination at the TiO2/PCBM/CH3NH3PbI3 interface. The devices composed of evaporated CH3NH3PbI3 on top of the TiO2/PCBM and [2,2',7,7'-tetrakis( N, N-di- p-methoxyphenyl-amine)-9,9'-spirobifluorene] (Spiro-OMeTAD) as hole-transport material demonstrated power conversion efficiencies of 17.1% (reverse scan) and 13.4% (forward scan) with stabilized efficiency of over 16%, which is, to the best of our knowledge, the highest efficiency reported for evaporated perovskite solar cells using low-temperature fabrication method involving compact TiO2 layer as ETL. Furthermore, we show that this process can be used to deposit a CH3NH3PbI3 layer on top of a textured silicon substrate, which is the first step for preparing perovskite-silicon tandem devices with enhanced antireflection and light-trapping properties.

6.
Adv Mater ; 30(8)2018 Feb.
Article in English | MEDLINE | ID: mdl-29318666

ABSTRACT

Organometal halide perovskites have attracted widespread attention as the most favorable prospective material for photovoltaic technology because of their high photoinduced charge separation and carrier transport performance. However, the microstructural aspects within the organometal halide perovskite are still unknown, even though it belongs to a crystal system. Here direct observation of the microstructure of the thin film organometal halide perovskite using transmission electron microscopy is reported. Unlike previous reports claiming each phase of the organometal halide perovskite solely exists at a given temperature range, it is identified that the tetragonal and cubic phases coexist at room temperature, and it is confirmed that superlattices composed of a mixture of tetragonal and cubic phases are self-organized without a compositional change. The organometal halide perovskite self-adjusts the configuration of phases and automatically organizes a buffer layer at boundaries by introducing a superlattice. This report shows the fundamental crystallographic information for the organometal halide perovskite and demonstrates new possibilities as promising materials for various applications.

7.
Sci Rep ; 7(1): 14685, 2017 10 31.
Article in English | MEDLINE | ID: mdl-29089627

ABSTRACT

Highly transparent and stretchable Ag nanowire (NW)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hybrid electrodes were prepared on stretchable polyurethane substrates by using simple and cost-effective brush painting technique. The optimized Ag NW/PEDOT:PSS hybrid electrode showed a sheet resistance of 19.7 Ohm/square and a high optical transmittance of 88.64% comparable to conventional ITO electrode. It was found that shear stress of the paintbrush led to an effective lateral alignment of the Ag NWs into the PEDOT:PSS matrix during brush painting process. In addition, we investigated mechanical properties of the brush painted Ag NW/PEDOT:PSS hybrid electrode using inner/outer bending test, stretching tests, twisting test and rolling test in detail. The optimized brush painted Ag NW/PEDOT:PSS electrode showed a higher strain (~30%) than brush painted Ag NW or sputtered ITO electrode. Furthermore, we demonstrated the outstanding stretchability of brush painted Ag NW/PEDOT:PSS hybrid electrode in two applications: stretchable interconnectors and stretchable electrodes for stretchable and wearable thin film heaters. These results provide clear evidence for its potential and widespread applications in next-generation, stretchable displays, solar cells, and electronic devices.

8.
Article in English | MEDLINE | ID: mdl-28761499

ABSTRACT

Cordyceps militaris is used widely as a traditional medicine in East Asia. Although a few studies have attempted to elucidate the anticancer activities of C. militaris, the precise mechanism of C. militaris therapeutic effects is not fully understood. We examined the anticancer activities of C. militaris ethanolic extract (Cm-EE) and its cellular and molecular mechanisms. For this purpose, a xenograft mouse model bearing murine T cell lymphoma (RMA) cell-derived cancers was established to investigate in vivo anticancer mechanisms. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, immunoblotting analysis, and flow cytometric assay were employed to check in vitro cytotoxicity, molecular targets, and proapoptotic action of Cm-EE. Interestingly, cancer sizes and mass were reduced in a C. militaris-administered group. Levels of the phosphorylated forms of p85 and AKT were clearly decreased in the group administered with Cm-EE. This result indicated that levels of phosphoglycogen synthase kinase 3ß (p-GSK3ß) and cleaved caspase-3 were increased with orally administered Cm-EE. In addition, Cm-EE directly inhibited the viability of cultured RMA cells and C6 glioma cells. The number of proapoptotic cells was significantly increased in a Cm-EE treated group compared with a control group. Our results suggested that C. militaris might be able to inhibit cancer growth through regulation of p85/AKT-dependent or GSK3ß-related caspase-3-dependent apoptosis.

9.
Medicine (Baltimore) ; 96(25): e7174, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28640096

ABSTRACT

RATIONALE: Transforaminal epidural glucocorticoids administration is widely performed for the management of lumbosacral radiculopathy. However, it may worsen the condition of patients with type 2 diabetes mellitus (DM). Polydeoxyribonucleotide (PDRN) was recently noted as a substitute for glucocorticoids. PATIENT CONCERNS: A 44-year-old male patient was admitted to our pain clinic with symptoms of low back pain with severe pain and tingling sensation of left posterolateral leg. He had type 2 DM medicated with Glimepiride and Metformin. Blood glucose level was 367 mg/dL. He declined to use glucocorticoid. DIAGNOSES: He was diagnosed as left foraminal disc protrusion at L4-5, left subarticular disc protrusion at L5-S1. INTERVENTIONS: Fluoroscopically guided transforaminal epidural PDRN injections were carried out. OUTCOMES: The patient was followed up for more than 6 months and demonstrated good improvement in lumbosacral radiculopathy without any complications. LESSONS: This is the first successful report on epidural injection of PDRN.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Intervertebral Disc Displacement/drug therapy , Low Back Pain/drug therapy , Polydeoxyribonucleotides/administration & dosage , Radiculopathy/drug therapy , Adult , Humans , Injections, Epidural , Intervertebral Disc Displacement/complications , Intervertebral Disc Displacement/diagnostic imaging , Low Back Pain/diagnostic imaging , Low Back Pain/etiology , Lumbar Vertebrae/diagnostic imaging , Male , Radiculopathy/diagnostic imaging , Radiculopathy/etiology , Sacrum/diagnostic imaging
10.
Sci Rep ; 7: 46739, 2017 04 24.
Article in English | MEDLINE | ID: mdl-28436426

ABSTRACT

We report on semi-transparent stretchable Ag films coated on a wavy-patterned polydimethylsiloxane (PDMS) substrate for use as stretchable electrodes for stretchable and transparent electronics. To improve the mechanical stretchability of the Ag films, we optimized the wavy-pattern of the PDMS substrate as a function of UV-ozone treatment time and pre-strain of the PDMS substrate. In addition, we investigated the effect of the Ag thickness on the mechanical stretchability of the Ag electrode formed on the wavy-patterned PDMS substrate. The semi-transparent Ag films formed on the wavy-patterned PDMS substrate showed better stretchability (strain 20%) than the Ag films formed on a flat PDMS substrate because the wavy pattern effectively relieved strain. In addition, the optical transmittance of the Ag electrode on the wavy-patterned PDMS substrate was tunable based on the degree of stretching for the PDMS substrate. In particular, it was found that the wavy-patterned PDMS with a smooth buckling was beneficial for a precise patterning of Ag interconnectors. Furthermore, we demonstrated the feasibility of semi-transparent Ag films on wavy-patterned PDMS as stretchable electrodes for the stretchable electronics based on bending tests, hysteresis tests, and dynamic fatigue tests.

11.
J Colloid Interface Sci ; 486: 287-295, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27721077

ABSTRACT

Reduced graphene oxide (rGO)/thorn-like TiO2 nanofiber (TTF) aerogels, or GTTF aerogels, with different TTF weight ratios were successfully prepared by electrospinning, silica etching and hydrothermal combination method. During the hydrothermal reaction, the rGO nanosheets and TTF self-assembled into three-dimensional (3D) interconnected networks, in which the TTF is loaded onto the rGO nanosheets. The electrochemical performance of the GTTF aerogels was assessed using cyclic voltammetry and galvanostatic charge-discharge measurements in a 1M aqueous Na2SO4 electrolyte. The TTF-to-rGO ratio of the aerogel material significantly affected the electrochemical performance of the aerogel electrodes, and the GTTF aerogels prepared with 20wt% TTF (denoted GTTF-20) exhibited excellent electrochemical performance. The maximum specific capacitance of this aerogel electrode was 178F/g at a current density of 1A/g. The GTTF-20 aerogel also exhibited good electrochemical stability with a capacitance degradation of less than 10% after 3000cycles. We can deduce that the electrochemical performance of the as-prepared aerogels may be enhanced by increasing the chemical interactions between rGO and TiO2. The results indicate that the GTTF aerogels show enormous potential for application in energy storage devices.

12.
Sci Rep ; 6: 34322, 2016 Sep 28.
Article in English | MEDLINE | ID: mdl-27677410

ABSTRACT

We report fabrication of large area Ag nanowire (NW) film coated using a continuous roll-to-roll (RTR) slot die coater as a viable alternative to conventional ITO electrodes for cost-effective and large-area flexible touch screen panels (TSPs). By controlling the flow rate of shear-thinning Ag NW ink in the slot die, we fabricated Ag NW percolating network films with different sheet resistances (30-70 Ohm/square), optical transmittance values (89-90%), and haze (0.5-1%) percentages. Outer/inner bending, twisting, and rolling tests as well as dynamic fatigue tests demonstrated that the mechanical flexibility of the slot-die coated Ag NW films was superior to that of conventional ITO films. Using diamond-shape patterned Ag NW layer electrodes (50 Ohm/square, 90% optical transmittance), we fabricated 12-inch flexible film-film type and rigid glass-film-film type TSPs. Successful operation of flexible TSPs with Ag NW electrodes indicates that slot-die-coated large-area Ag NW films are promising low cost, high performance, and flexible transparent electrodes for cost-effective large-area flexible TSPs and can be substituted for ITO films, which have high sheet resistance and are brittle.

13.
Biomol Ther (Seoul) ; 24(6): 595-603, 2016 Nov 01.
Article in English | MEDLINE | ID: mdl-27469142

ABSTRACT

(E)-3-Phenyl-1-(2-pyrrolyl)-2-propenone (PPP) is a pyrrole derivative of chalcone, in which the B-ring of chalcone linked to ß-carbon is replaced by pyrrole group. While pyrrole has been studied for possible Src inhibition activity, chalcone, especially the substituents on the B-ring, has shown pharmaceutical, anti-inflammatory, and anti-oxidant properties via inhibition of NF-κB activity. Our study is aimed to investigate whether this novel synthetic compound retains or enhances the pharmaceutically beneficial activities from the both structures. For this purpose, inflammatory responses of lipopolysaccharide (LPS)-treated RAW264.7 cells were analyzed. Nitric oxide (NO) production, inducible NO synthase (iNOS) and tumor necrosis factor-α (TNF-α) mRNA expression, and the intracellular inflammatory signaling cascade were measured. Interestingly, PPP strongly inhibited NO release in a dose-dependent manner. To further investigate this anti-inflammatory activity, we identified molecular pathways by immunoblot analyses of nuclear fractions and whole cell lysates prepared from LPS-stimulated RAW264.7 cells with or without PPP pretreatment. The nuclear levels of p50, c-Jun, and c-Fos were significantly inhibited when cells were exposed to PPP. Moreover, according to the luciferase reporter gene assay after cotransfection with either TRIF or MyD88 in HEK293 cells, NF-κB-mediated luciferase activity dose-dependently diminished. Additionally, it was confirmed that PPP dampens the upstream signaling cascade of NF-κB and AP-1 activation. Thus, PPP inhibited Syk, Src, and TAK1 activities induced by LPS or induced by overexpression of these genes. Therefore, our results suggest that PPP displays anti-inflammatory activity via inhibition of Syk, Src, and TAK1 activity, which may be developed as a novel anti-inflammatory drug.

14.
Article in English | MEDLINE | ID: mdl-25918546

ABSTRACT

The Cordyceps species have been widely used for treating various cancer diseases. Although the Cordyceps species have been widely known as an alternative anticancer remedy, which compounds are responsible for their anticancer activity is not fully understood. In this study, therefore, we examined the anticancer activity of 5 isolated compounds derived from the butanol fraction (Cb-BF) of Cordyceps bassiana. For this purpose, several cancer cell lines such as C6 glioma, MDA-MB-231, and A549 cells were employed and details of anticancer mechanism were further investigated. Of 5 compounds isolated by activity-guided fractionation from BF of Cb-EE, KTH-13, and 4-isopropyl-2,6-bis(1-phenylethyl)phenol, Cb-BF was found to be the most potent antiproliferative inhibitor of C6 glioma and MDA-MB-231 cell growth. KTH-13 treatment increased DNA laddering, upregulated the level of Annexin V positive cells, and altered morphological changes of C6 glioma and MDA-MB-231 cells. In addition, KTH-13 increased the levels of caspase 3, caspase 7, and caspase 9 cleaved forms as well as the protein level of Bax but not Bcl-2. It was also found that the phosphorylation of AKT and p85/PI3K was also clearly reduced by KTH-13 exposure. Therefore, our results suggest KTH-13 can act as a potent antiproliferative and apoptosis-inducing component from Cordyceps bassiana, contributing to the anticancer activity of this mushroom.

15.
Phytother Res ; 29(3): 381-92, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25414115

ABSTRACT

Gouania leptostachya DC. var. tonkinensis Pitard. Rhamnaceae is a traditional medicinal plant used in Thailand for treating various inflammatory symptoms. However, no systematic studies have been performed concerning the anti-inflammatory effects or molecular mechanisms of this plant. The immunopharmacological activities of a methanol extract from the leaves and twigs of G. leptostachya (Gl-ME) were elucidated based on the gastritis symptoms of mice treated with HCl/EtOH and the inflammatory responses, such as nitric oxide (NO) release and prostaglandin E2 (PGE2) production, from RAW264.7 cells and peritoneal macrophages. Moreover, inhibitory target molecules were also assessed. Gl-ME dose-dependently diminished the secretion of NO and PGE2 from LPS-stimulated RAW264.7 cells and peritoneal macrophages. The gastritis lesions of HCl/EtOH-treated mice were also attenuated after Gl-ME treatment. The extract (50 and 300 µg/mL) clearly reduced mRNA expression of inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, nuclear translocation of p65/nuclear factor (NF)-κB, phosphorylation of p65-activating upstream enzymes, such as protein kinase B (AKT), inhibitor of κBα kinase (IKK), and inhibitor of κB (IκBα), and the enzymatic activity of Src. By HPLC analysis, one of the major components in the extract was revealed as resveratrol with NO and Src inhibitory activities. Moreover, this compound suppressed NO production and HCl/EtOH-induced gastric symptoms. Therefore, these results suggest that Gl-ME might be useful as an herbal anti-inflammatory medicine through the inhibition of Src and NF-κB activation pathways. The efficacy data of G. leptostachya also implies that this plant could be further tested to see whether it can be developed as potential anti-inflammatory preparation.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Macrophages, Peritoneal/drug effects , Plant Extracts/pharmacology , Rhamnaceae/chemistry , Stilbenes/pharmacology , Animals , Cell Line , Cyclooxygenase 2/metabolism , Dinoprostone/metabolism , Gastritis/drug therapy , I-kappa B Proteins/metabolism , Lipopolysaccharides/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , NF-KappaB Inhibitor alpha , NF-kappa B/metabolism , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Resveratrol , Thailand
16.
J Ethnopharmacol ; 159: 9-16, 2015 Jan 15.
Article in English | MEDLINE | ID: mdl-25446596

ABSTRACT

ETHNOPHARMACOLOGIC RELEVANCE: Persicaria chinensis L. (Polygonaceae) [also synonym as Polygonum chimnense L.] has been used as Chinese traditional medicine to treat ulcer, eczema, stomach ache, and various inflammatory skin diseases. Due to no molecular pharmacological evidence of this anti-inflammatory herbal plant, we investigated the inhibitory mechanisms and target proteins contributing to the anti-inflammatory responses of the plant by using its methanolic extract (Pc-ME). MATERIALS AND METHODS: We used lipopolysaccharide (LPS)-treated macrophages and a murine HCl/EtOH-induced gastritis model to evaluate the anti-inflammatory activity of Pc-ME. HPLC analysis was employed to identify potential active components of this extract. Molecular approaches including kinase assays, reporter gene assays, immunoprecipitation analysis, and overexpression of target enzymes were used to confirm target enzymes. RESULTS: Pc-ME inhibited LPS-induced nitric oxide and prostaglandin E2 release by RAW264.7 macrophages and ameliorated HCl/EtOH-induced gastric ulcers in mice. The nuclear translocation of NF-κB (p65 and p50) was suppressed by Pc-ME. Phosphorylation of Src and Syk, their kinase activities, and formation of the signaling complex of these proteins were repressed by Pc-ME. Phosphorylation of p85 and Akt induced by Src or Syk overexpression was blocked by Pc-ME. In the mouse gastritis model, orally administered Pc-ME suppressed the increased phosphorylation of IκBα, Αkt, Src, and Syk. Caffeic acid, kaempferol, and quercetin, identified as major anti-inflammatory components of Pc-ME by HPLC, displayed strong nitric oxide inhibitory activity in LPS-treated macrophages. CONCLUSION: Pc-ME might play a pivotal ethnopharmacologic role as an anti-inflammatory herbal medicine by targeting Syk and Src kinases and their downstream transcription factor NF-κB.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Plant Extracts/pharmacology , Polygonum , Protein Kinase Inhibitors/pharmacology , Animals , Anti-Inflammatory Agents/therapeutic use , Cell Line , Cell Survival/drug effects , Cells, Cultured , Ethanol , Flavonoids/isolation & purification , Flavonoids/pharmacology , Flavonoids/therapeutic use , Gastritis/chemically induced , Gastritis/drug therapy , HEK293 Cells , Humans , Hydrochloric Acid , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins/metabolism , Lipopolysaccharides , Macrophages , Male , Methanol/chemistry , Mice, Inbred C57BL , Mice, Inbred ICR , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Phytotherapy , Plant Extracts/therapeutic use , Protein Kinase Inhibitors/therapeutic use , Protein-Tyrosine Kinases/antagonists & inhibitors , Protein-Tyrosine Kinases/metabolism , Solvents/chemistry , Syk Kinase , src-Family Kinases/antagonists & inhibitors , src-Family Kinases/metabolism
17.
Article in English | MEDLINE | ID: mdl-25132860

ABSTRACT

The inhibitory activities of the Cordyceps pruinosa butanol fraction (Cp-BF) were investigated by determining inflammatory responses of lipopolysaccharide (LPS)-treated RAW264.7 macrophage cells and by evaluating HCl/ethanol (EtOH)-triggered gastric ulcers in mice. The molecular mechanisms of the inhibitory effects of Cp-BF were investigated by identifying target enzymes using biochemical and molecular biological approaches. Cp-BF strongly inhibited the production of NO and TNF-α, release of reactive oxygen species (ROS), phagocytic uptake of FITC-dextran, and mRNA expression levels of interleukin (IL)-6, inducible NO synthase (iNOS), and tumour necrosis factor-alpha (TNF)-α in activated RAW264.7 cells. Cp-BF also strongly downregulated the NF-κB pathway by suppressing IKKß according to luciferase reporter assays and immunoblot analysis. Furthermore, Cp-BF blocked both increased levels of NF-κB-mediated luciferase activities and phosphorylation of p65/p50 observed by IKKß overexpression. Finally, orally administered Cp-BF was found to attenuate gastric ulcer and block the phosphorylation of IκBα induced by HCl/EtOH. Therefore, these results suggest that the anti-inflammatory activity of Cp-BF may be mediated by suppression of IKKα and its downstream NF-κB activation. Since our group has established the mass cultivation conditions by developing culture conditions for Cordyceps pruinosa, the information presented in this study may be useful for developing new anti-inflammatory agents.

18.
J Ethnopharmacol ; 152(3): 487-96, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24503036

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia asiatica Nakai (Compositae) is a representative herbal plant used to treat infection and inflammatory diseases. Although Artemisia asiatica is reported to have immunopharmacological activities, the mechanisms of these activities and the effectiveness of Artemisia asiatica preparations in use are not known. MATERIALS AND METHODS: To evaluate the anti-inflammatory activities of Artemisia asiatica ethanol extract (Aa-EE), we assayed nitric oxide (NO), tumor necrosis factor (TNF)-α, and prostaglandin E2 (PGE2) in macrophages and measured the extent of tissue injury in a model of gastric ulcer induced in mice by treatment with HCl in EtOH. Putative enzymatic mediators of Aa-EE activities were identified by nuclear fractionation, reporter gene assay, immunoprecipitation, immunoblotting, and kinase assay. Active compound in Aa-EE was identified using HPLC. RESULTS: Treatment of RAW264.7 cells and peritoneal macrophages with Aa-EE suppressed the production of NO, PGE2, and TNF-α in response to lipopolysaccharide (LPS) and induced heme oxygenase-1 expression. The Aa-EE also ameliorated symptoms of gastric ulcer in HCl/EtOH-treated mice. These effects were associated with the inhibition of nuclear translocation of nuclear factor (NF)-κB and activator protein (AP)-1, implying that the anti-inflammatory action of the Aa-EE occurred through transcriptional inhibition. The upstream regulatory signals Syk and Src for translocation of NF-κB and TRAF6 for AP-1 were identified as targets of this effect. Analysis of Aa-EE by HPLC revealed the presence of luteolin, known to inhibit NO and PGE2 activity. CONCLUSION: The anti-inflammatory activities attributed to Artemisia asiatica Nakai in traditional medicine may be mediated by luteolin through inhibition of Src/Syk/NF-κB and TRAF6/JNK/AP-1 signaling pathways.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Artemisia/chemistry , Inflammation/drug therapy , Plant Extracts/pharmacology , Animals , Anti-Inflammatory Agents/isolation & purification , Dinoprostone/metabolism , Disease Models, Animal , Ethanol/chemistry , Inflammation/pathology , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Male , Medicine, Traditional , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , NF-kappa B/metabolism , Stomach Ulcer/drug therapy , Stomach Ulcer/pathology , Transcription Factor AP-1/metabolism , Tumor Necrosis Factor-alpha/metabolism
19.
J Ethnopharmacol ; 151(3): 1165-1174, 2014 Feb 12.
Article in English | MEDLINE | ID: mdl-24378351

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Myrsine seguinii H. LÉVEILLÉ (syn. Rapanea neriifolia) (Myrsinaceae) is a medicinal plants traditionally used in Myanmar to treat infectious and inflammatory diseases. Since none of reports have systematically demonstrated the anti-inflammatory activity of this plant, we aimed to mechanistically understand the regulatory roles of the plant in inflammatory responses using the ethanolic extract of Myrsine seguinii (Ms-EE). MATERIALS AND METHODS: Activated macrophages and peritonitis symptoms induced by lipopolysaccharide (LPS) were employed. HPLC analysis was used to identify active components. To characterize direct target enzymes, kinase assay was established. RESULTS: Ms-EE inhibited the production of nitric oxide (NO) and prostaglandin (PG)E2 in RAW264.7 cells and peritoneal macrophages stimulated by LPS. This extract suppressed the mRNA expression of the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 genes by down-regulating the activation of nuclear factor (NF)-κB and activator protein (AP-1). Interestingly, it was found that Ms-EE can directly suppress the enzyme activities of Syk, Src, and interleukin-1 receptor-associated kinase-1 (IRAK-1). Similarly, orally administered Ms-EE inhibited the phosphorylation of Src and Syk in peritoneal exudate-derived cells prepared from peritonitis. Finally, HPLC analysis clearly demonstrated that quercetin is a major active component with suppressing activity on the release of inflammatory mediators (NO and PGE2), and the enzyme activities of Src, Syk, and IRAK-1. CONCLUSION: Ms-EE containing quercetin negatively modulates macrophage-mediated in vitro inflammatory responses and LPS-induced peritonitis by blocking the Src/Syk/NF-κB and IRAK-1/AP-1 pathways, which contributes to its major ethnopharmacological use as an anti-inflammatory herbal medicine.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Peritonitis/drug therapy , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Primulaceae , Animals , Cell Line , Cell Survival/drug effects , Dinoprostone/metabolism , Ethanol/chemistry , Humans , Interleukin-1 Receptor-Associated Kinases/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , Lipopolysaccharides , Macrophage Activation/drug effects , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/immunology , Male , Mice , Mice, Inbred C57BL , Nitric Oxide/metabolism , Peritonitis/metabolism , Phytotherapy , Plant Leaves , Plant Stems , Protein-Tyrosine Kinases/metabolism , Solvents/chemistry , Syk Kinase , src-Family Kinases/metabolism
20.
J Ethnopharmacol ; 151(2): 960-9, 2014 Feb 03.
Article in English | MEDLINE | ID: mdl-24342777

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Cerbera manghas L. (Apocynaceae), a semi-mangrove medicinal plant distributed throughout tropical and subtropical countries, is traditionally known to possess analgesic, anti-inflammatory, anti-convulsant, cardiotonic, and hypotensive activity. In vitro and in vivo anti-inflammatory activities of a methanol extract of the leaves of Cerbera manghas and the underlying molecular mechanisms were investigated to validate the ethnopharmacological use of this plant. MATERIALS AND METHODS: The effect of Cerbera manghas methanol extract (Cm-ME) on the production of inflammatory mediators and the induction of HCl/EtOH-treated gastritis was explored using macrophages, HEK293 cells, and ICR mice. The molecular targets of this extract and potential active components in Cm-ME were also investigated. RESULTS: Cm-ME inhibited the production of nitric oxide (NO) in lipopolysaccharide (LPS)-treated RAW264.7 cells and peritoneal macrophages in a dose-dependent manner. This extract also suppressed the expression of NO synthase (iNOS) and cyclooxygenase (COX)-2. NF-κB-mediated enhancement of luciferase activity, nuclear translocation of p50 and p65, and phosphorylation of IκBα were markedly reduced by Cm-ME treatment. Direct enzyme assays, reporter gene assays, and immunoprecipitation analysis of kinases revealed Syk and Src as immunopharmacological targets of Cm-ME. Moreover, this extract strongly ameliorated the gastric symptoms induced by HCl/EtOH treatment of mice. Finally, HPLC analysis and pharmacological tests identified kaempferol as an active component of the extract with Src/Syk inhibitory activities. CONCLUSION: Inhibition of Syk/Src and the NF-κB pathway by kaempferol could play a key role in the anti-inflammatory pharmacological action of Cerbera manghas.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Apocynaceae , Intracellular Signaling Peptides and Proteins/metabolism , Plant Extracts/pharmacology , Protein-Tyrosine Kinases/metabolism , src-Family Kinases/metabolism , Animals , Anti-Inflammatory Agents/therapeutic use , Apocynaceae/chemistry , Cell Line , Cells, Cultured , Cyclooxygenase 2/genetics , Ethanol , Gastritis/chemically induced , Gastritis/drug therapy , HEK293 Cells , Humans , Hydrochloric Acid , Kaempferols/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Male , Methanol/chemistry , Mice , Mice, Inbred C57BL , Mice, Inbred ICR , NF-kappa B/metabolism , Nitric Oxide/pharmacology , Nitric Oxide Synthase Type II/genetics , Plant Extracts/therapeutic use , RNA, Messenger/metabolism , Solvents/chemistry , Syk Kinase
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