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Jiayu Tang,
Jianming Guo,
Jingjing Fan,
Cheng Qian, Feifei Tao,
Xiang Zhou,
Xuefeng Wu,
Yang Sun,
Jianxin Li,
Yan Shen,
Qiang Xu
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ABSTRACT: Astilbin, a natural flavonoid, has been shown to have a selective immunosuppressive activity on activated T lymphocytes. In our previous study, 3'-O-methylastilbin was identified as an active metabolite in vivo. However, more comprehensive information regarding the kinetics and metabolic characteristics of astilbin is yet unknown. Here, we isolated and identified 4 metabolites after incubating astilbin with rat liver microsomal/cytosolic fractions. Besides 3'-O-methylastilbin, 4'-O-methylastilbin was firstly identified and detected in the rat plasma after either oral or intravenous administration of astilbin. And phenotypic differences in the metabolic profile were observed between the two administration routes when using UPLC/MS(E) to measure the metabolites in the plasma. Moreover, 4'-O-methylastilbin decreased serum transaminases elevation in mice with concanavalin A-induced liver injury and reduced the mRNA expression of TNF-alpha and IFN-gamma in primed lymph cells upon antigen restimulation. The immunosuppressive activity of 4'-O-methylastilbin appears weaker than astilbin and 3'-O-methylastilbin. Taken together, the characterization of the comprehensive metabolic profile of astilbin confirmed 3'-O-methylastilbin as the major active form of astilbin metabolites, revealed 4'-O-methylastilbin as a minor active form, and helped us to evaluate the route of astilbin administration, which is beneficial for the treatment of human immune diseases.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences 04/2013; 929C:56-62. · 2.78 Impact Factor
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Wen Liu,
Wenjie Guo,
Jing Wu,
Qiong Luo, Feifei Tao,
Yanhong Gu,
Yan Shen,
Jianxin Li,
Renxiang Tan,
Qiang Xu,
Yang Sun
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ABSTRACT: NLRP3 inflammasome has been reported to be associated with various kinds of immunological diseases including colitis. However, there are few drug candidates targeting inflammasomes for the treatment of colitis. In the present study, we aimed at examining the effect of 1-ethyl-5-methyl-2-phenyl-1H-benzo[d]imidazole, a synthetic small molecular compound also named Fc11a-2, for the treatment of dextran sulfate sodium (DSS)-induced experimental colitis in mice via targeting NLRP3 inflammasome. Treatment with Fc11a-2 dose-dependently attenuated the loss of body weight and shortening of colon length induced by DSS. In addition, the disease activity index, histopathologic scores and myeloperoxidase activity were also significantly reduced by Fc11a-2 treatment. Moreover, protein and mRNA levels of DSS-induced proinflammatory cytokines in colon, including TNF-α, IL-1β, IL-18, IL-17A and IFN-γ, were markedly suppressed by Fc11a-2. Furthermore, a decreased CD11c(+) macrophage infiltration in colons and inactivation of caspase-1 in peritoneal macrophages were detected in Fc11a-2-treated mice. The mechanism of action of Fc11a-2 was related to the inhibition of the cleavage of pro-caspase-1, pro-IL-1β and pro-IL-18 which in turn suppressed the activation of NLRP3 inflammasome. Taken together, our results demonstrate the ability of Fc11a-2 to inhibit NLRP3 inflammasome activation and its potential use in the treatment of inflammatory bowel diseases.
Biochemical pharmacology 03/2013; · 4.25 Impact Factor
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ABSTRACT: Inflammatory bowel disease (IBD) is a chronic inflammatory disorder in the intestine which involves overproduction of pro-inflammatory cytokines and excessive functions of inflammatory cells. However, current treatments for IBD may have potential adverse effects including steroid dependence, infections and lymphoma. Therefore new therapies or drug candidates for the treatment of IBD are desperately needed. In the present study we found that icariin, a major bioactive compound from plants in Epimedium family, exerted protective effect on intestinal inflammation in mice induced by dextran sulfate sodium. Oral administration of icariin significantly attenuated the disease progression and alleviated the pathological changes of colitis. It also inhibited the production of pro-inflammatory cytokines and expression of p-p65, p-STAT1 and p-STAT3 in colon tissues. Further study showed that icariin dose-dependently inhibited the proliferation and activation of T lymphocytes, and suppressed pro-inflammatory cytokine levels of activated T cells. Moreover, icariin treatment inhibited the phosphorylations of STAT1 and STAT3 in CD4(+) T cells, which were the crucial transcription factors for Th1 and Th17 respectively. Taken together, these results indicate that icariin is a potential therapeutic agent for IBD.
Biochemical pharmacology 12/2012; · 4.25 Impact Factor
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ABSTRACT: Allograft rejection is a predominantly Th1 immune response. In this study, we showed that obaculactone, a natural compound derived from citrus fruit, prolonged skin graft survival in mice when treated after but not before transplantation. Furthermore, obaculactone inhibited alloantigen-specific production of Th1 cytokine IFN-gamma as well as proinflammatory cytokine IL-2, TNFalpha and IL-6. In parallel, IL-10 production was markedly up-regulated. Obaculactone significantly enhanced the percentage of CD4(+)CD25(+)Foxp3(+) Treg cells in the CD4(+) splenocytes without any effect on their inhibitory function. In vitro and in vivo tests showed obaculactone down-regulated T-bet expression in Th1 effector cells. Taken together, the unique immunomodulatory properties might qualify obaculactone as a putative, therapeutic compound for the treatment of Th1-driven diseases, including transplant rejection.
Biochemical pharmacology 03/2010; 80(2):218-25. · 4.25 Impact Factor
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ABSTRACT: The ordered arrays of magnetic metal (including Fe, Co and Ni) nanotubes and nanowires encapsulated with carbon tubes are controllably synthesized by employing the array of C tubes as second-order template and combining with electrodeposition technique. The wall thickness and diameter of carbon nanotubes are uniform along the whole tubes; also the wall thickness of inner metal nanotubes is adjustable from 25 nm to solid nanowires. These composite structures are characterized by X-ray diffractometer (XRD), energy-dispersive spectrometry (EDS), Raman scattering spectrum, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The magnetic properties show that coaxial nanotubes and nanocables composite arrays all exhibit magnetic anisotropy with the easy direction perpendicular to axis of the metal nanotubes or nanowires except the Ni at C coaxial nanotubes array that has no preferable magnetization axis.
Journal of Nanoscience and Nanotechnology 10/2008; 8(9):4494-4499. · 1.56 Impact Factor
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ABSTRACT: We have developed a template-free hydrothermal method of constructing rare earth phosphate hollow spheres using H(6)P(4)O(13) as the PO(4) (3-) source. The mechanism of hollow spheres formation was proposed on the basis of Ostwald ripening. The resulting hollow spheres, especially with the aid of doping of other lanthanide cations, exhibit emission spanning the whole UV-visible wavelength range.
Langmuir 07/2008; 24(15):8280-3. · 4.19 Impact Factor
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ABSTRACT: We for the first time report the synthesis of urchinlike BiPO4 structure composed of nanorods and its photoluminescence properties. Scanning electron microscopy (SEM) images show urchinlike BiPO4 structure composed of nanorods. The X-ray powder diffraction (XRD) pattern indicates that the crystal structure of the nanorod is monoclinic. The high-resolution transmission electron microscopy (HRTEM) image and Fast-Fourier-transform (FFT) pattern reveal the single-crystalline nature of the nanorod. The formation mechanism was proposed. BiPO4 displays strong blue emission. Because of the similarities of the crystal structure and lattice constants and the suitable energy level with the rare-earth phosphate, BiPO4 is a useful host for rare-earth ions. Ln3+ is successfully doped in BiPO4 and an efficient energy transfer from Bi3+ to Ln3+ takes place, which makes BiPO4:Ln (Ln = Eu, Tb, Dy) emit strong luminescence in visible region. BiPO4:Ln will have promising application in high-performance luminescence devices, etc.
06/2008;
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ABSTRACT: The β-Ni(OH)2 microtubes with hierarchical structure wall composed of interweaved nanolamella were successfully fabricated by the template-free wet-chemical approach. To the best of our knowledge, it is the first report on Ni(OH)2 microtubes with the micro- and nanoscale composite structure. This method is very facile and effective to prepare the tubular materials with high yield and uniform tube diameter. The intermediate product and final composite structures were well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform IR (FTIR), and thermogravimetric analysis (TGA), and the formation mechanism was deeply studied. In comparison with β-Ni(OH)2 microrod and particle electrodes, β-Ni(OH)2 microtube electrode has the highest discharge capacity in alkaline battery, indicating the potential applications of the microtubes with the hierarchical structures in alkaline Ni-based batteries, supercapacitor, and catalytic areas.
06/2008;
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ABSTRACT: Lanthanide phosphate microspheres composed of single-crystal CePO4 and CePO4:Tb nanorods were successfully synthesized, respectively, using the functionalized composite aggregate as a template, which is composed of P123, H6P4O13 and Ce3+, and also as a resource of reaction species with high chemical potential. The shape and the phase structure of the CePO4 nanocrystal can be easily controlled via adjusting reaction temperature, monomer concentration and annealing temperature. SEM images show the spherical superstructure composed of nanorods. HRTEM and SAED images reveal the single-crystalline nature of nanorod and TEM images show the hollow interiors of the superstructure. XRD patterns indicate that the crystal structure of the nanorods is hexagonal before and monoclinic after annealing. The formation mechanism was proposed. Strong UV and green luminescence were observed for the CePO4 and CePO4:Tb microspheres, respectively. The synthesis method can be extended to the fabrication of NRHS and core–shell microspheres of other rare-earth or doped LnPO4 materials for wide applications.
Nanotechnology 09/2007; 18(41):415602. · 3.98 Impact Factor
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ABSTRACT: Cuprous oxide 3-D ordered macroporous material was constructed by electrochemical deposition using a polystyrene colloidal crystal as template. The highly ordered macroporous structure with a hexagonal array can be extended over hundreds of square micrometers. The photonic stop bands of both the PS colloidal crystal and Cu2O 3DOM were found. Due to the highly ordered porous structure, the optical absorption and the charge carrier transportation are better in Cu2O 3DOM than in bulk Cu2O, which makes the reduction of oxygen faster on Cu2O 3DOM than on bulk Cu2O under visible light illumination. The higher photocurrent efficiency under visible light illumination makes the 3DOM Cu2O more suitable for solar applications.
Journal of Colloid and Interface Science 05/2007; 308(2):460-5. · 3.07 Impact Factor
