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11.
《Phytomedicine》2014,21(5):704-711
Extract of Acanthopanax senticosus harms (EAS) has been shown to have neuroprotective effects on dopaminergic neurons in Parkinson's disease (PD) mice model. α-Synuclein is a key player in the pathogenesis of PD, the elevated level of which is deleterious to dopaminergic neurons, and enhancing its clearance might be a promising strategy for treating PD. To assess the potential of EAS in this regard, we investigated its effect on the SH-SY5Y cells overexpressing wild-type α-synuclein (WT-α-Syn) or A53T mutant α-synuclein (A53T-α-Syn), and the implicated pathway it might mediate. After treatment with EAS, the changes of α-synuclein, caspase-3, parkin, phospho-protein kinase B (Akt), phospho-glycogen synthase kinase 3 beta (GSK3β), and phospho-microtubule-associated protein tau (Tau) in WT-α-Syn or A53T-α-Syn transgenic cells were reverted back to near normal levels, demonstrated by the western blotting and quantitative real-time PCR outcomes. The neuroprotective effects of EAS may be able to protect WT-α-Syn or A53T-α-Syn transgenic SH-SY5Y cells from α-synuclein overexpression and toxicity. Therefore, we speculate that EAS might be a promising candidate for prevention or treatment of α-synuclein-related neurodegenerative disorders such as PD. 相似文献
12.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):1105-1112
Nine novel 4-[3-(4-Dimethylamino-phenyl)-5-aryl-4,5-dihydro-pyrazol-1-yl]-benzenesulfonamides (2a-i) were synthesized and evaluated for their anti-inflammatory and antiproliferative activities. These compounds (2a-i) showed moderate to strong anti-inflammatory activity in carrageenan rat paw oedema test. Compounds 2b, 2d and 2g showing comparable anti-inflammatory activity to that of reference drug celecoxib were evaluated for their ulcerogenic and analgesic activities. The effect of 2b, 2d and 2g on the content of NO, TNF-α and PGE2 in exudates from rat paw stimulated by carrageenan was also evaluated. The compound 2c showed considerable antitumor activities against all 60 human tumor cell lines with effective GI50 (MG-MID) value of 3.63 µM. It exhibited maximum activity against melanoma (LOX IMVI and SK-MEL-5) cancer cell lines with GI50 value less than 2 μM. 相似文献
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14.
Izumi Tabata Yoriko Atomi Hiroaki Kanehisa Mitsumasa Miyashita 《European journal of applied physiology and occupational physiology》1990,60(4):254-258
The purpose of this study was to determine the effects of high-intensity endurance training on isokinetic muscle power. Six male students majoring in physical-education participated in high intensity endurance training on a cycle ergometer at 90% of maximal oxygen uptake (VO2max) for 7 weeks. The duration of the daily exercise session was set so that the energy expenditure equalled 42 kJ.kg-1 of lean body mass. Peak knee extension power was measured at six different speeds (30 degrees, 60 degrees, 120 degrees, 180 degrees, 240 degrees, and 300 degrees.s-1) with an isokinetic dynamometer. After training, VO2max increased significantly from mean values of 51.2 ml.kg-1.min-1, SD 6.5 to 56.3 ml.kg-1.min-1, SD 5.3 (P less than 0.05). Isokinetic peak power at the lower test speeds (30 degrees, 60 degrees and 120 degrees.s-1) increased significantly (P less than 0.05). However, no significant differences in muscle peak power were found at the faster velocities of 180 degrees, 240 degrees, and 300 degrees.s-1. The percentage improvement was dependent on the initial muscle peak power of each subject and the training stimulus (intensity of cycle ergometer exercise). 相似文献
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Fruits of tomato incorporated [2-14C]mevalonic acid lactone into the steroidal glycoalkaloid α-tomatine. Young fruits showed the greatest alkaloid-synthesizing ability but this decreased as the fruits developed. Analysis of sap exuded from fruit stalks and also application of[4-14C]cholesterol to leaves confirmed that tomatine is not transported into fruits from vegetative organs. Accumulation of this alkaloid in fruits thus appears entirely due to synthesis. Excised fruits of all developmental stages degraded injected [14C]tomatine and rates were directly related to fruit age. The pattern of accumulation/decline in fruit tomatine may be explicable on the basis of changing capacity for synthesis/degradation during development. Label from injected [14C]tomatine was present mainly in chlorophylls and carotenoids where it increased with time as that in tomatine decreased. The significance of the relationship between tomatine disappearance and carotenoid development is briefly discussed. The aglycone tomatidine was not detected in green fruits but a Δ16-5α-pregnenolone-like compound was. 相似文献
17.
A new method which utilizes Procion Red MX 2B amylopectin for the detection of α-amylase in crude plant extracts is described. The substrate is specific only against α-amylase hydrolysis and β-amylase does not attack it. Paper containing Procion Red MX 2B amylopectin applied to gels after isoelectric focusing reveals α-amylase isoenzymes as white bands. When this technique is used, heat-inactivation of β-amylase is not required. 相似文献
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19.
P Midoux J P Grivet F Delmotte M Monsigny 《Biochemical and biophysical research communications》1984,119(2):603-611
The synthesis of N-acetyl- and N-trifluoroacetyl-glucosaminides was reported. The interaction of these compounds with wheat germ agglutinin, a plant lectin specific for N-acetyl-glucosamine and sialic acid, was investigated by two complementary approaches: 1H and 19F NMR, and fluorescence spectroscopy. This last technique relies on the existence of a competitive equilibrium involving the protein, the ligand and O-(methylumbelliferyl)-N-acetyl-glucosaminide, a fluorescent saccharide. The binding constants and the chemical shifts in the complex were determined and were related to the protein structure. 相似文献
20.
Inhibition of ornithine decarboxylase induces embryonal carcinoma cell differentiation 总被引:2,自引:0,他引:2
J Schindler M Kelly P P McCann 《Biochemical and biophysical research communications》1983,114(1):410-417
Murine embryonal carcinoma cells can be induced to differentiate in vitro by various physical and chemical means. We report here that inhibition of ornithine decarboxylase activity with a specific enzyme-activated inhibitor, alpha-difluoromethylornithine, can induce differentiation in embryonal carcinoma cells. The differentiated phenotype can be distinguished from undifferentiated embryonal carcinoma cells by altered cellular morphology, biochemical and cell surface antigenic properties. These results suggest that alterations in the levels of cellular polyamines may play a role in embryonal carcinoma cell differentiation. 相似文献