Ellagic acid inhibits oxidized low-density lipoprotein (OxLDL)-induced metalloproteinase (MMP) expression by modulating the protein kinase C-α/extracellular signal-regulated kinase/peroxisome proliferator-activated receptor γ/nuclear factor-κB (PKC-α/ERK/PPAR-γ/NF-κB) signaling pathway in endothelial cells     

Kuo MY  Ou HC  Lee WJ  Kuo WW  Hwang LL  Song TY  Huang CY  Chiu TH  Tsai KL  Tsai CS  Sheu WH 《Journal of agricultural and food chemistry》2011,59(9):5100-5108

Previous studies have shown that vascular endothelium-derived matrix metalloproteinases (MMPs) contribute to the destabilization of atherosclerotic plaques, a key event triggering acute myocardial infarction. In addition, studies have reported that the PKC-MEK-PPARγ signaling pathway is involved in oxidized low-density lipoprotein (oxLDL)-induced expression of MMPs. Ellagic acid, a phenolic compound found in fruits and nuts, has potent antioxidant, anti-inflammatory, and anticancerous properties. However, the molecular mechanisms underlying its antiatherogenic effects remain to be clarified. This study aimed to assess whether the effects of ellagic acid on the fibrotic markers MMP-1 and MMP-3 are modulated by the PKC-ERK-PPAR-γ signaling pathway in human umbilical vein endothelial cells (HUVECs) that have been exposed to oxLDL. It was found that ellagic acid significantly inhibited oxLDL-induced expressions of MMP-1 and MMP-3. Pretreatment with ellagic acid and DPI, a well-known ROS inhibitor, attenuated the oxLDL-induced expression and activity of PKC-α. In addition, ellagic acid as well as pharmacological inhibitors of ROS, calcium, and PKC strongly suppressed the oxLDL-induced phosphorylation of extracellular signal-regulated kinase (ERK) and NF-κB activation. Moreover, ellagic acid ameliorated the oxLDL-induced suppression of PPAR-γ expression. In conclusion, the data suggest that ellagic acid elicits its protective effects by modulating the PKC-α/ERK/PPAR-γ/NF-κB pathway, resulting in the suppression of ROS generation and, ultimately, inhibition of MMP-1 and MMP-3 expression in HUVECs exposed to oxLDL.  相似文献   

New Hydroquinone Monoterpenoid and Cembranoid-Related Metabolites from the Soft Coral Sarcophyton tenuispiculatum     

Tzu-Yin Huang  Chiung-Yao Huang  Shu-Rong Chen  Jing-Ru Weng  Tzu-Hsuan Tu  Yuan-Bin Cheng  Shih-Hsiung Wu  Jyh-Horng Sheu 《Marine drugs》2021,19(1)

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Bioactive cembranoids from the soft coral Sinularia crassa     

Chao CH  Chou KJ  Huang CY  Wen ZH  Hsu CH  Wu YC  Dai CF  Sheu JH 《Marine drugs》2011,9(10):1955-1968

Eight new cembranoids, crassarines A-H (1-8) were isolated from the Formosan soft coral Sinularia crassa. Compounds 1-3 represent the rare cembranoids with a 1,12-oxa-bridged tetrahydrofuran ring, while 4 and 5 are the firstly discovered 1,11-oxa-bridged tetrahydropyranocembranoids. The absolute configuration of 6 was determined using the Mosher's method. Compounds 6 and 8 were found to significantly inhibit the expression of both pro-inflammatory iNOS and COX-2 proteins at 10 μM, respectively, while compounds 4-8 were found to be non-cytotoxic toward the selected human liver cancer cells.  相似文献   

Antioxidant activity of extracts from <Emphasis Type="Italic">Calocedrus formosana</Emphasis> leaf,bark, and heartwood     

Sheng-Yang?Wang  Jyh-Horng?Wu  Sen-Sung?Cheng  Chiu-Ping?Lo  Hsing-Ning?Chang  Lie-Fen?Shyur  Shang-Tzen?ChangEmail author 《Journal of Wood Science》2004,50(5):422-426

Calocedrus formosana Florin (Cupressaceae) is an endemic tree to Taiwan. To evaluate the antioxidant activity of the plant extracts from heartwood, bark, and leaf of C. formosana, assays for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities, as well as prevention of DNA strand cleavage were performed in this study. Similar IC₅₀ values against the DPPH radical were found for the heartwood and bark extracts at approximately 23µg/ml. Moreover, the heartwood extract exhibited the highest inhibitory activity against superoxide radicals among the test samples; a 2.3-fold lower value of IC₅₀ for superoxide radical inhibition was found in the heartwood extract relative to that of (+)-catechin. Much less effect on inhibition of DPPH and superoxide radicals was found from the leaf extract of C. formosana. More than 70% of superoxide radicals were inhibited in the presence of 10µg/ml heartwood extract, whereas only 15% inhibition was obtained from the leaf extract. The heartwood extract, at a dose of approximately 0.5mg/ml, apparently completely prevented the X174 supercoiled DNA cleavage induced by ultraviolet photolysis of H₂O₂, as judged by agarose gel electrophoresis. This report also suggests that the antioxidant activities of the plant extracts of C. formosana are in good correlation with their phenolic contents.  相似文献   

Effects of chromated-phosphate treatment process on the green color protection of ma bamboo ( Dendrocalamus latiflorus )     

Shang-Tzen Chang  Jyh-Horng Wu  Ting-Feng Yeh 《Journal of Wood Science》2002,48(3):227-231

Ma bamboo (Dendrocalamus latiflorus Munro) treated with chromated phosphate (CP) exhibits an excellent green color. To understand the effects of the treatment sequence of CrO₃ and H₃PO₄ and their interactions regarding green color protection, CrO₃-H₃PO₄ and H₃PO₄-CrO₃ two-step treatments plus a H₃PO₄-CrO₃-H₃PO₄ three-step treatment were carried out in this study. Results revealed that the treatment sequence of CrO₃ and H₃PO₄ definitely affects the effectiveness of bamboo color protection. Green color protection of ma bamboo culm could not be achieved by treating it with CrO₃ or H₃PO₄ alone or with the H₃PO₄-CrO₃ two-step treatment. Only by treating it with the CrO₃-H₃PO₄ two-step treatment or the H₃PO₄-CrO₃-H₃PO₄ three-step treatment did ma bamboo exhibit an excellent green color. The results indicated that bamboo reacts first with CrO₃ and then forms an insoluble complex with H₃PO₄, which produces the green color on its epidermis. Chlorophyll analyses demonstrated that chlorophyll is not a key factor for green color protection. The green pigment was also formed when chlorophyll-free bamboo was treated with 2% CP at 60°C for 3h.  相似文献   

Green-color conservation of ma bamboo (Dendrocalamus latiflorus) treated with chromium-based reagents     

Shang-Tzen Chang  Jyh-Horng Wu 《Journal of Wood Science》2000,46(1):40-44

The objectives of this study were to search for appropriate chemical reagents without arsenic to use as green-color protectors for ma bamboo (Dendrocalamus latiflorus Munro) culms and to compare the effectiveness of these reagents for green-color conservation. Bamboo culms treated with chromated copper phosphate (CCP) or chromated phosphate (CP), which were developed by us, exhibit a greener color than those treated with Boliden K-33 (type B chromated copper arsenate).The experimental results revealed that among the chemicals employed, CrO₃ and H₃PO₄ were key components in conserving the green color of bamboo epidermis, and their ratio definitely affected the effectiveness of green-color conservation. When the CrO₃/H₃PO₄ ratio was 11, the treated bamboo culms displayed the greenest color. Among all the bamboo culms treated with different formulations of inorganic salts, the one treated with CP (1% CrO₃, 1% H₃PO₄) had the best green-color conservation, enhanced by increasing the duration of treatment.  相似文献   

Development and characterization of a potential diagnostic monoclonal antibody against capsid protein VP1 of the chicken anemia virus     

Yi-Yang Lien  Chi-Hung Huang  Fang-Chun Sun  Shyang-Chwen Sheu  Tsung-Chi Lu  Meng-Shiunn Lee  Shu-Chin Hsueh  Hsi-Jien Chen  Meng-Shiou Lee 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(1):73-79

Chicken anemia virus (CAV) is an important viral pathogen that causes anemia and severe immunodeficiency syndrome in chickens worldwide. In this study, a potential diagnostic monoclonal antibody against the CAV VP1 protein was developed which can precisely recognize the CAV antigen for diagnostic and virus recovery purposes. The VP1 gene of CAV encoding the N-terminus-deleted VP1 protein, VP1Nd129, was cloned into an Escherichia (E.) coli expression vector. After isopropyl-β-D-thiogalactopyronoside induction, VP1Nd129 protein was shown to be successfully expressed in the E. coli. By performing an enzyme-linked immunoabsorbent assay using two coating antigens, purified VP1Nd129 and CAV-infected liver tissue lysate, E3 monoclonal antibody (mAb) was found to have higher reactivity against VP1 protein than the other positive clones according to the result of limiting dilution method from 64 clones. Using immunohistochemistry, the presence of the VP1-specific mAb, E3, was confirmed using CAV-infected liver and thymus tissues as positive-infected samples. Additionally, CAV particle purification was also performed using an immunoaffinity column containing E3 mAb. The monoclonal E3 mAb developed in this study will not only be very useful for detecting CAV infection and performing histopathology studies of infected chickens, but may also be used to purify CAV particles in the future.  相似文献   

C-phycocyanin, a very potent and novel platelet aggregation inhibitor from Spirulina platensis     

Hsiao G  Chou PH  Shen MY  Chou DS  Lin CH  Sheu JR 《Journal of agricultural and food chemistry》2005,53(20):7734-7740

The aim of this study was to systematically examine the inhibitory mechanisms of C-phycocyanin (C-PC), one of the major phycobiliproteins of Spirulina platensis (a blue-green alga), in platelet activation. In this study, C-PC concentration-dependently (0.5-10 nM) inhibited platelet aggregation stimulated by agonists. C-PC (4 and 8 nM) inhibited intracellular Ca2+ mobilization and thromboxane A2 formation but not phosphoinositide breakdown stimulated by collagen (1 microg/mL) in human platelets. In addition, C-PC (4 and 8 nM) markedly increased levels of cyclic GMP and cyclic GMP-induced vasodilator-stimulated phosphoprotein (VASP) Ser(157) phosphorylation. Rapid phosphorylation of a platelet protein of Mw 47,000 (P47), a marker of protein kinase C activation, was triggered by phorbol-12,13-dibutyrate (150 nM). This phosphorylation was markedly inhibited by C-PC (4 and 8 nM). In addition, C-PC (4 and 8 nM) markedly reduced the electron spin resonance (ESR) signal intensity of hydroxyl radicals in collagen (1 microg/mL)-activated platelets. The present study reports on a novel and very potent (in nanomolar concentrations) antiplatelet agent, C-PC, which is involved in the following inhibitory pathways: (1) C-phycocyanin increases cyclic GMP/VASP Ser157 phosphorylation and subsequently inhibits protein kinase C activity, resulting in inhibition of both P47 phosphorylation and intracellular Ca2+ mobilization, and (2) C-PC may inhibit free radicals (such as hydroxyl radicals) released from activated platelets, which ultimately inhibits platelet aggregation. These results strongly indicate that C-PC appears to represent a novel and potential antiplatelet agent for treatment of arterial thromboembolism.  相似文献   

Water repellency and warmth retention finishes for polyester fabrics based on hybrid materials comprising zirconia,silica, and thiazole dyes prepared via sol-gel synthesis     

Chien-Wen Chen  Mu-Cheng Kuo  Jyh-Horng Wu  Ming-Shien Yen  Sing-You Lai 《Fibers and Polymers》2017,18(10):1945-1955

A series of hybrid materials composed of zirconia, silica, and thiazole dyes were synthesized from zirconium npropoxide (ZNP) and tetraethoxysilane (TEOS) using heteroaryl 2-amino-thiazole azo dyes, and prepared via the sol-gel process. The heterocyclic 2-amino-thiazole azo dyes underwent a hydrolysis-condensation reaction with an appropriate proportion of ZNP under a catalyst, using a constant ratio of vinyltriethoxysilane (VTES) and TEOS. The structures of these hybrid materials composed of zirconia/silica/thiazole dyes were characterized using Fourier transform infrared (FT-IR) analysis. The surface morphologies of the polyethylene terephthalate (PET) fabrics were evaluated using scanning electron microscopy (SEM). The SEM images demonstrated the uniform dyeing of the PET fabrics, which confirmed the reaction of the hybrid materials with the PET fabrics. The water contact angle, washing fastness, color uniformity, and warmth retention of the PET fabrics dyed with the hybrid materials composed of the zirconia/silica/thiazole dyes were evaluated. The evaluation results indicated that these fabrics offered enhanced warmth retention properties and good water repellency.  相似文献   

Anomalous scattering study of the bi distribution in the 2212 superconductor: implications for cu valency     

Lee P  Gao Y  Sheu HS  Petricek V  Restori R  Coppens P  Darovskikh A  Phillips JC  Sleight AW  Subramanian MA 《Science (New York, N.Y.)》1989,244(4900):62-63

The distribution of the bismuth atoms over the cation sites in the 2212 Bi-Sr-Ca-Cu-O superconductor has been determined by anomalous scattering synchrotron crystallography. The analysis of reflection pairs measured at wavelengths of 0.9243 and 0.9600 angstrom shows a delocalization of the bismuth atoms over the calcium and strontium sites. The "mixed" plane between the CuO(2) layers contains 6.0(1.4) percent bismuth (where the number in brackets represents the statistical standard deviation derived from the least-squares refinement of the data), and a much smaller amount of strontium than often assumed. The strontium deficiency is charge-compensated by the creation of electron holes in the CuO(2) layer. The result supports the view that neither extra oxygen nor overlap of the bismuth 6p and copper 3d bands is needed to account for the holes, which are an essential feature of the superconductivity mechanism.  相似文献