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991.
Won Yong Seo Ha Yong Song Ah Ra Goh Young-Hee Kang Jinseu Park 《Biochemical and biophysical research communications》2010,398(1):140-540
Celastrol, a quinone methide triterpenoid derived from the medicinal plant Tripterygium wilfordii, possesses various biological activities such as anti-oxidant, anti-tumor, and anti-inflammatory activities. In this study, we examined the suppressive effect of celastrol on IFN-γ-induced expression of ICAM-1 and the molecular mechanism responsible for these activities. We found that celastrol induced mRNA and protein expression of heme oxygenase-1 (HO-1) in the human keratinocyte cell line HaCaT. Treatment of HaCaT cells with tin protoporphyrin IX (SnPP), a specific inhibitor of HO-1, reversed the suppressive effect of celastrol on IFN-γ-induced protein and mRNA expression of ICAM-1. HO-1 knockdown using small interfering RNA (siRNA) led to reverse inhibition of IFN-γ-induced up-regulation of ICAM-1 by celastrol. In addition, SnPP reversed suppression of IFN-γ-induced promoter activity of ICAM-1 by celastrol. Furthermore, blockage of HO-1 activity by SnPP and HO-1 siRNA reversed the inhibitory effect of celastrol on IFN-γ-induced adhesion of monocytes to keratinocytes. These results suggest that celastrol may exert anti-inflammatory responses by suppressing IFN-γ-induced expression of ICAM-1 and subsequent monocyte adhesion via expression of HO-1 in the keratinocytes. 相似文献
992.
Jee In Kim Sang Won Jung Kwon Moo Park In Kyeom Kim 《Biochemical and biophysical research communications》2010,399(3):452-457
A temporal increase in temperature triggers a series of stress responses and alters vascular smooth muscle (VSM) contraction induced by agonist stimulation. Here we examined the role of reactive oxygen species (ROS) in heat shock-dependent augmentation of angiotensin II (AngII)-induced VSM contraction. Endothelium-denuded rat aortic rings were treated with heat shock for 45 min at 42 °C and then subjected to assays for the production of force, ROS, and the expression of ROS-related enzymes. AngII-induced contraction was enhanced in heat shock-treated aorta. AngII-induced production of hydrogen peroxide and superoxide were elevated in response to the heat shock treatment. Pre-treatment with superoxide dismutases (SOD) mimetic and inhibitors for glutathione peroxidase and NADPH oxidase but not for xanthine oxidase eliminated an increase in the AngII-induced contraction in the heat shock-treated aorta. Heat shock increased the expression of p47phox, a cytosolic subunit of NADPH oxidase, but not Cu-Zn-SOD and Mn-SOD. In addition, heat shock increased contraction that was evoked by hydrogen peroxide and pyrogallol. These results suggest that heat shock causes an elevation of ROS as well as a sensitization of ROS signal resulting in an augmentation of VSM contraction in response to agonist. 相似文献
993.
Jae Hong Park Bong Geun Chung Won Gu Lee Jinseok Kim Mark D. Brigham Jaesool Shim Seunghwan Lee Chang Mo Hwang Naside Gozde Durmus Utkan Demirci Ali Khademhosseini 《Biotechnology and bioengineering》2010,106(1):138-148
In this article, we describe an approach to generate microporous cell‐laden hydrogels for fabricating biomimetic tissue engineered constructs. Micropores at different length scales were fabricated in cell‐laden hydrogels by micromolding fluidic channels and leaching sucrose crystals. Microengineered channels were created within cell‐laden hydrogel precursors containing agarose solution mixed with sucrose crystals. The rapid cooling of the agarose solution was used to gel the solution and form micropores in place of the sucrose crystals. The sucrose leaching process generated homogeneously distributed micropores within the gels, while enabling the direct immobilization of cells within the gels. We also characterized the physical, mechanical, and biological properties (i.e., microporosity, diffusivity, and cell viability) of cell‐laden agarose gels as a function of engineered porosity. The microporosity was controlled from 0% to 40% and the diffusivity of molecules in the porous agarose gels increased as compared to controls. Furthermore, the viability of human hepatic carcinoma cells that were cultured in microporous agarose gels corresponded to the diffusion profile generated away from the microchannels. Based on their enhanced diffusive properties, microporous cell‐laden hydrogels containing a microengineered fluidic channel can be a useful tool for generating tissue structures for regenerative medicine and drug discovery applications. Biotechnol. Bioeng. 2010; 106: 138–148. © 2010 Wiley Periodicals, Inc. 相似文献
994.
Hong Wei Wang Hyuk Jin Kwon Won Cheol Yim Sung Don Lim Jun-Cheol Moon Byung-Moo Lee Yong Weon Seo Wook Kim Cheol Seong Jang 《Genetica》2010,138(8):843-852
Previously, the wheat non-specific lipid transfer proteins (TaLTP), members of a small multigene family, were reported to
evidence a complex pattern of expression regulation. In order to assess further the expression diversity of the TaLTP genes, we have attempted to evaluate their expression profiles in responses to abiotic stresses, using semi-quantitative
RT-PCR. The expression profiles generated herein revealed that the TaLTP genes in group A evidenced highly similar responses against abiotic stresses, whereas differential expression patterns among
genes in each group were also observed. A total of seven promoters were fused to a GUS reporter gene and the recombinants
were introduced into Arabidopsis, while three promoters evidenced non-detectible GUS activity. The promoters of TaLTP1, TaLTP7, and TaLTP10 included in group A drove strong expressions during plant development with overlapping patterns, in large part, but also
exhibited distinct expression pattern, thereby suggesting subfunctionalization processing over evolutionary time. However,
only trace expression in cotyledons, young emerged leaves, and epidermal cell layers of flower ovaries was driven by the promoter
of TaLTP3 of group B. These results indicate that their distinct physiological functions appear to be accomplished by a subfunctionalization
process involving degenerative mutations in regulatory regions. 相似文献
995.
Sushila Maharjan Je Won Park Yeo Joon Yoon Hei Chan Lee Jae Kyung Sohng 《Biotechnology letters》2010,32(2):277-282
Using metabolic engineering, we developed Streptomyces venezuelae YJ028 as an efficient heterologous host to increase the malonyl-CoA pool to be directed towards enhanced production of various
polyketides. To probe the applicability of newly developed hosts in the heterologous production of polyketides, we expressed
type III polyketide synthase, 1,3,6,8-tetrahydroxynaphthalene synthase, in these hosts. Flaviolin production was doubled by
expression of acetyl-CoA carboxylase (ACCase) and 4-fold by combined expression of ACCase, metK1-sp and afsR-sp. Thus, the newly developed Streptomyces venezuelae YJ028 hosts produce heterologous polyketides more efficiently than the parent strain. 相似文献
996.
Oh WJ Wu CC Kim SJ Facchinetti V Julien LA Finlan M Roux PP Su B Jacinto E 《The EMBO journal》2010,29(23):3939-3951
The mechanisms that couple translation and protein processing are poorly understood in higher eukaryotes. Although mammalian target of rapamycin (mTOR) complex 1 (mTORC1) controls translation initiation, the function of mTORC2 in protein synthesis remains to be defined. In this study, we find that mTORC2 can colocalize with actively translating ribosomes and can stably interact with rpL23a, a large ribosomal subunit protein present at the tunnel exit. Exclusively during translation of Akt, mTORC2 mediates phosphorylation of the nascent polypeptide at the turn motif (TM) site, Thr450, to avoid cotranslational Akt ubiquitination. Constitutive TM phosphorylation occurs because the TM site is accessible, whereas the hydrophobic motif (Ser473) site is concealed in the ribosomal tunnel. Thus, mTORC2 can function cotranslationally by phosphorylating residues in nascent chains that are critical to attain proper conformation. Our findings reveal that mTOR links protein production with quality control. 相似文献
997.
The protective effects of catechin 7-O-β-D glucopyranoside (C7G) against streptozotocin (STZ)-induced mitochondrial damage in rat pancreatic β-cells (RINm5F) were investigated. A marked increase in mitochondrial reactive oxygen species (ROS) was observed in STZ-treated cells; this increase was restricted by C7G treatment. C7G also scavenged superoxide anions and hydroxyl radicals generated by xanthine/xanthine oxidase (xanthine/XO) and the Fenton reaction (FeSO(4) + H(2) O(2)), respectively. C7G restored activity and expression of both mitochondrial manganese superoxide dismutase (MnSOD) and catalase (CAT), which were suppressed by STZ treatment. In addition, C7G prevented STZ-induced mitochondrial lipid peroxidation, protein carbonyl, and DNA base modification. C7G restored the loss of mitochondrial membrane potential (Δψ) that was disrupted by STZ treatment, and prevented cell death via inhibition of apoptosis. These results suggest that C7G has a protective effect against STZ-induced cell damage by its antioxidant effects and the attenuation of mitochondrial dysfunction. 相似文献
998.
Choong Hyun Lee In Koo Hwang Jung Hoon Choi Ki-Yeon Yoo Tae Hee Han Ok Kyu Park So Yeong Lee Pan Dong Ryu Moo-Ho Won 《Cellular and molecular neurobiology》2010,30(3):333-338
In this study, we examined changes in immunoreactivities of calcium binding proteins, such as parvalbumin (PV), calbindin
(CB), and calretinin (CR), in the rat basolateral amygdala (BLA) 14 days after myocardial infarction (MI). In the MI-operated
group, numbers of PV and CB immunoreactive (+) neurons in the BLA were significantly reduced compared to those in the sham-operated group. However, numbers of CR+ neurons were slightly, not significantly, reduced in the MI-operated group. These results indicate that MI may decrease the
immunoreactivities of PV and CB, not CR, in the rat BLA. 相似文献
999.
Nguyen Xuan Cuong Nguyen Xuan Nhiem Nguyen Phuong Thao Nguyen Hoai Nam Nguyen Tien Dat Hoang Le Tuan Anh Le Mai Huong Phan Van Kiem Chau Van Minh Ji-Hee Won Won-Yoon Chung Young Ho Kim 《Bioorganic & medicinal chemistry letters》2010,20(16):4782-4784
Ten phenolic compounds (1–10) were isolated from a methanol extract of Lawsonia inermis leaves including two new ones, lawsoniasides A (1) and B (2). Their structures were elucidated by spectroscopic methods (NMR and FTICRMS) in combination with acid hydrolysis and GC analyses. Compounds 4 and 5 showed a significant inhibition on receptor activator for nuclear factor-κB ligand-induced osteoclast formation in murine bone-marrow macrophages. 相似文献
1000.