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81.
Acute and fulminant liver failure induced by viral hepatitis, alcohol or other hepatotoxic drugs are associated with tumor necrosis factor (TNF) production. D-Galactosamine (D-GalN) and lipopolysaccharide (LPS)-induced liver injury is an experimental model of fulminant hepatic failure. In this model, TNF-alpha plays a central role in the pathogenesis of D-GalN/LPS-induced liver injury in mice. Y-40138, N-[1-(4-[4-(pyrimidin-2-yl)piperazin-1-yl]methyl phenyl)cyclopropyl] acetamide.HCl inhibits TNF-alpha and augments interleukin (IL)-10 production in LPS-injected mice in plasma. In the present study, we examined the effect of Y-40138 on D-GalN/LPS-induced hepatitis. Y-40138 (10mg/kg, i.v.) significantly suppressed TNF-alpha and monocyte chemoattractant protein-1 (MCP-1) production and augmented IL-10 production in plasma. In addition, Y-40138 significantly inhibited TNF-alpha production induced by direct interaction between human T lymphocytes and macrophages. Y-40138 suppressed plasma alanine transaminase (ALT) elevation and improved survival rate in D-GalN/LPS-injected mice, and it is suggested that the protective effect of Y-40138 on hepatitis may be mediated by inhibition of TNF-alpha and MCP-1, and/or augmentation of IL-10. This compound is expected to be a new candidate for treatment of cytokine and/or chemokine-related liver diseases such as alcoholic hepatitis. 相似文献
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83.
Chaperone-like activities of alpha-synuclein: alpha-synuclein assists enzyme activities of esterases
Ahn M Kim S Kang M Ryu Y Kim TD 《Biochemical and biophysical research communications》2006,346(4):1142-1149
Alpha-synuclein, a major constituent of Lewy bodies (LBs), has been implicated to play a critical role in the pathogenesis of Parkinson's disease (PD), although the physiological function of alpha-synuclein has not yet been known. Here we have shown that alpha-synuclein, which has no well-defined secondary or tertiary structure, can protect the enzyme activity of microbial esterases against stress conditions such as heat, pH, and organic solvents. In particular, the flexibility of alpha-synuclein and its C-terminal region seems to be important for complex formation, but the structural integrity of the C-terminal region may not be required for stabilization of enzyme activity. In addition, atomic force microscopy (AFM) and in vivo enzyme assays showed highly specific interactions of esterases with alpha-synuclein. Our results indicate that alpha-synuclein not only protects the enzyme activity of microbial esterases in vitro, but also can stabilize the active conformation of microbial esterases in vivo. 相似文献
84.
Siamopoulou P Bimplakis A Iliopoulou D Vagias C Cos P Vanden Berghe D Roussis V 《Phytochemistry》2004,65(14):2025-2030
Nineteen secondary metabolites of the brown alga Dictyota dichotoma (Huds.) Lam. and fifteen metabolites of the brown alga D. linearis (Ag.) Grev. were isolated and their chemical structures were elucidated on the basis of their NMR and mass spectral data. The diterpenes isopachydictyolal (1) from D. dichotoma and 4alpha-acetyldictyodial (2) from D. linearis are new natural products. The antiviral activity of metabolites isolated in adequate amounts was evaluated in laboratory assays against Herpes simplex virus I (HSV I) and Poliomyelitis Virus I, using Vero cells as hosts. 相似文献
85.
Konstandi M Kostakis D Harkitis P Johnson EO Marselos M Adamidis K Lang MA 《Life sciences》2006,79(4):331-341
CYP1A2, a principal catalyst for metabolism of various therapeutic drugs and carcinogens, among others, is in part regulated by the stress response. This study was designed to assess whether catecholamines and in particular adrenergic receptor-dependent pathways, modulate benzo(alpha)pyrene (B(alpha)P)-induced hepatic CYP1A2. To distinguish between the role of central and peripheral catecholamines in the regulation of CYP1A2 induction, the effect of central and peripheral catecholamine depletion using reserpine was compared to that of peripheral catecholamine depletion using guanethidine. The effects of peripheral adrenaline and L-DOPA administration were also assessed. The results suggest that alterations in central catecholamines modulate 7-methoxyresorufin O-demethylase activity (MROD), CYP1A2 mRNA and protein levels in the B(alpha)P-induced state. In particular, central catecholamine depletion, dexmedetomidine-induced inhibition of noradrenaline release and blockade of alpha(1)-adrenoceptors with prazosin, up-regulated CYP1A2 expression. Phenylephrine and dexmedetomidine-induced up-regulation may be mediated, in part, via peripheral alpha(1)- and alpha(2)-adrenoceptors, respectively. On the other hand, the L-DOPA-induced increase in central dopaminergic activity was not followed by any change in the up-regulation of CYP1A2 expression by B(alpha)P. Central noradrenergic systems appeared to counteract up-regulating factors, most likely via alpha(1)- and alpha(2)-adrenoceptors. In contrast, peripheral alpha- and beta-adrenoceptor-related signaling pathways are linked to up-regulating processes. The findings suggest that drugs that bind to adrenoceptors or affect central noradrenergic neurotransmission, as well as factors that challenge the adrenoceptor-linked signaling pathways may deregulate CYP1A2 induction. This, in turn, may result in drug-therapy and drug-toxicity complications. 相似文献
86.
目的:研究TGF-α、TGF-β1与胰腺癌临床病理的关系.方法:免疫组织化学SABC法检测41例胰腺癌组织和12例正常胰腺组织中TGF-α、TGF-β1的表达情况,并分析其与病人的年龄、性别、肿瘤部位、病理分级和分期(UICC)等指标的相关性.结果:在41例胰腺癌组织中TGF-αTGF-β1的阳性表达率分别为73.2%、63.4%,在12例正常胰腺组织中的阳性表达率分别为16.7%、25.0%,两组之间存在显著差异(P=0.001).在胰腺癌组织中,TGF-β1的表达在不同分期中存在显著差异(P=0.019);TGF-α的表达与胰腺癌患者的年龄、性别、肿瘤部位、大小、分期及组织学分级无相关性(P>0.05).结论:TGF-α、TGF-β1在胰腺癌中高表达.TGF-β1与胰腺癌病理分期有关. 相似文献
87.
Akira Isogai Akinori Suzuki Shizuo Higashkawa Shimpei Kuyama Saburo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(12):3033-3035
( + )-α-Kainic acid (1) was synthesized by starting from a building block, N-Boc-3-acetoxyallylglycine ethyl ester (2). The key intermediate, a methyl 4-[(tert-butoxycarbonyl)prenylamino]-5-hydroxy-2-pentenoate derivative (9), was prepared from 2 in eight synthetic steps. After converting 10 into a methyl ester (11), intramolecular ene-carbocyclization of 11 gave a pyrrolidine derivative (12), which was converted to 1 in a moderate yield. 相似文献
88.
《Bioscience, biotechnology, and biochemistry》2013,77(10):1905-1907
Asymmetric trans-esterification of meso-2,5-dibromoadipate to (–)-benzyl methyl 2,5-dibromoadipate by lipase with subsequent chemical reactions afforded optically active cis-2,5-disubstituted pyrrolidines. An equivalent asymmetric transformation was performed by selectively hydrolyzing a cis-2,5-disubstituted pyrrolidine having a chiral N-substituent. 相似文献
89.
90.
Mehdi Khoshneviszadeh Mohammad H. Ghahremani Alireza Foroumadi Ramin Miri Omidreza Firuzi Armin Madadkar-Sobhani Najmeh Edraki Maliheh Parsa Abbas Shafiee 《Bioorganic & medicinal chemistry》2013,21(21):6708-6717
A series of 16 novel 1,2,4-triazine derivatives bearing hydrazone moiety (7a–7p) have been designed, synthesized and evaluated for their activity to inhibit IL-1β and TNF-α production. All compounds are reported for the first time. The chemical structures of all compounds were confirmed by spectroscopic methods and elemental analyzes. Most of the synthesized compounds were proved to have potent anti-cytokine activity and low toxicity on PBMC and MCF-7 cell lines. Compounds 7f, 7k, 7l and 7j presented simultaneously good levels of inhibition of both cytokines. Moreover, compound 7l exhibited good anti-inflammatory effect in carrageenan-induced rat paw edema. The results of Western blotting demonstrated that the anti-cytokine potential of compound 7l is mainly mediated through the inhibition of p38 MAPK signaling pathway. Molecular docking was performed to position compound 7l into p38α binding site in order to explore the potential target. The information of this work might be helpful for the design and synthesis of novel scaffold toward the development of new therapeutic agent to fight against inflammatory diseases. 相似文献