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Metamizol is an analgesic and antipyretic agent that can induce agranulocytosis in certain patients. However, its effects on granulocyte viability and differentiation have been poorly evaluated. Here we analysed the effects of metamizol and its active metabolite, 4-methylaminoantipyrine (MAA), on the viability of HL60 promyelocytes and their dimethyl sulphoxide-induced differentiated granulocytes. Metamizol and MAA at 75 microM (above the peak of plasmatic concentration after 2g intake) did not alter granulocytic differentiation of HL60 cells. Only at concentrations above 100 microM, well over the pharmacological range, metamizol-induced apoptosis in about 30% of the HL60 promyelocytes, while HL60-granulocytic terminally differentiated cells were more resistant to this apoptotic action. When the effects of metamizol were compared with those of acetylsalicylic acid (ASA) and diclofenac on cell viability, at equivalent concentrations used in analgesic and antipyretic therapy (75 microM for metamizol, and ASA and 3 microM for diclofenac) their apoptotic effects were similar. Again, the HL60 promyelocytes were more sensitive to apoptosis than granulocytic differentiated cells, as measured by the percentage of sub-G(1) cells detected by flow cytometry and by determination of caspase activity as a function of poly(ADP-ribose) polymerase cleavage. Furthermore, when human blood-derived granulocytes were treated with metamizol, MAA, and ASA at 75 microM or diclofenac at 3 microM, less than 10% of apoptotic granulocytes were detected, whereas at toxicological/suprapharmacological concentrations (10mM), about 90% of granulocytes were apoptotic. These results demonstrate that metamizol, MAA, ASA, and diclofenac, at pharmacological concentrations, neither affect the granulocytic differentiation process nor induce relevant apoptosis on terminally differentiated granulocytes.  相似文献   
43.
胡朝暾  唐霞  肖震  付明  胡兴 《中草药》2016,47(13):2269-2276
目的研究茯苓发酵液中的蛋白质,对其进行分离与鉴定。方法采用液体发酵获得茯苓发酵液,Bradford法测定样品中蛋白质的质量浓度,有机酸沉淀法提取蛋白质,SDS-PAGE电泳分离蛋白质,蛋白质电泳片段进行胶内酶解、质谱分析和搜库鉴定。结果茯苓发酵液中蛋白质的质量浓度为74.01μg/m L,其相对分子质量(M)主要分布在2.8×104~1.3×105。通过质谱鉴定从茯苓发酵液中鉴定得到了51种蛋白质,如过氧化氢酶、蛋白激酶、碱性蛋白酶、糖化酶和溶菌酶等。结论茯苓发酵液中蛋白质种类丰富,是开展茯苓蛋白质研究及开发茯苓发酵保健食品与饮料的理想材料。  相似文献   
44.
Coptisine, an isoquinoline alkaloid isolated from rhizome of Coptis japonica, inhibits proliferation of vascular smooth muscle cells (VSMCs). The aim of this study was to evaluate the action of coptisine, along with berberine (a structurally similar isoquinoline alkaloid), on progression of the cell cycle in VSMCs. Coptisine displayed antiproliferative action against VSMCs by blocking the cell cycle at G(1) and G(2)/M phases. The G(1) block was shown by inhibition of [(3)H]thymidine incorporation into VSMCs at coptisine concentrations higher than 15 microM. The mechanism underlying the G(1) arrest involved a decrease in cyclin D1 protein, although cyclin E, A, and B were not affected by coptisine treatment. The selective reduction in cyclin D1 protein was mainly attributable to accelerated proteolysis via proteasome-dependent pathway, since it was inhibited by a proteasome inhibitor, N-carbobenzoxy-L-leucinyl-L-leucinyl-L-norleucinal (MG132) and further the mRNA level of cyclin D1, protein synthesis, and mitogen-activated protein kinase (MAPK) activity remained unaltered. The mechanism underlying the G(2)/M arrest involved partial inhibition of tubulin polymerization, which was apparent at coptisine concentration of 3 microM. Berberine arrested the cell cycle at G(1) phase via a mechanism identical with coptisine, but did not cause block at G(2)/M phase. The results demonstrate that a small difference in the structure between isoquinoline alkaloids produces a big difference in activity, and that coptisine has a unique double action in arresting the cell cycle of VSMCs.  相似文献   
45.
Benoxaprofen (BNX) has been implicated in rare but serious hepatotoxicity which led to its withdrawal from the world market. Flunoxaprofen (FLX), a structural analog, appears to be less toxic. It has been postulated that the nonsteroidal antiinflammatory drugs associated toxicity may be related to covalent modification of proteins by their reactive acyl glucuronides, and the extent of covalent protein binding depends on both reactivity of the acyl glucuronide and the exposure to the reactive metabolite. The disposition of BNX and FLX in rats were compared upon intravenous administration of 20 mg/kg of BNX, FLX or their metabolites. Covalent binding of BNX and FLX to plasma and liver proteins were also determined, and an immunochemical approach was used to detect their hepatic targets. Similar concentrations of plasma protein adducts for BNX and FLX were detected even though the AUC of BNX-glucuronide (BNX-G) was almost twice that of FLX-glucuronide (FLX-G). Similar concentrations of liver protein adducts for BNX and FLX were also detected at 8 h, however, the hepatobiliary exposure of BNX-G was only 1/3rd that of FLX-G indicating that BNX-G was more reactive than FLX-G, which was in agreement with in vitro data. Proteins of 110 and 70 kDa were the major liver protein targets modified by covalent attachment of BNX and FLX. In conclusion, measuring covalent binding to tissue proteins in animals in addition to plasma adducts should be considered when evaluating and comparing carboxylic acid analogs that form reactive acyl glucuronides.  相似文献   
46.
Velvet antler (VA), the unossified antler from members of the family Cervidae, has been used in traditional Chinese medicines and health foods for over 2000 years in enhancement of kidney function and treatment or prevention of cardiovascular, immunological and gynaecological disease. The aim of this study was to investigate the anti-inflammatory effect of velvet antler water extracts from Formosan sambar deer (Rusa unicolor swinhoei, SVAE) and red deer (Cervus elaphus, RVAE). Results indicated that both SVAE and RVAE significantly reduced the pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) productions in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells at concentrations above 200 μg mL?1. SVAE seems to demonstrate a better anti-inflammatory effect than that of RVAE in vitro. Both SVAE and RAVE also enhanced the anti-inflammatory cytokine IL-10 production in LPS-stimulated RAW 264.7 cells. The results of MTT assay indicated that SVAE and RVAE did not exhibit any cytotoxicity in LPS-stimulated RAW 264.7 cells. Two-dimensional (2D) gel electrophoresis analysis revealed that the levels of 6 specific proteins were different between these two velvet antlers samples. Furthermore, the storage period was the major factor affecting the anti-inflammatory activity of SAVE. In this study, we demonstrated the difference of anti-inflammatory effect and the protein profile between SVAE and RVAE. SVAE showed better anti-inflammatory potential than RVAE. In the future, the anti-inflammatory active components and their related mechanisms should be further investigated.  相似文献   
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48.
Although pharmacokinetic alternations by hepatic injury have been extensively studied, little is known about the potential influence of hepatoprotective agent's treatment. This study was aimed to investigate the holistic pharmacokinetics of multiple lignans, CYP3A regulations, and their correlations with hepatic injury biomarkers, in hepatic injured rats pretreated with or without schisandra lignan extract (SLE) and dimethyl-diphenyl-bicarboxylate (DDB). Integral pharmacokinetics of multiple lignans based on an AUC-weighting approach was determined in normal, CCl4 induced hepatic injury rats pretreated with or without SLE and DDB. Protein expression and activities of CYP3A were determined. Pharmacokinetic parameters and CYP3A activities were correlated with serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. CCl4 induced acute hepatic injury resulted in a nearly 8-fold enhancement of integral plasma exposures of multiple lignans, which was caused by the significant down-regulation of CYP3A. SLE and DDB pretreatment exhibited potent hepatoprotective effects, accompanied with the restored expression and activity of CYP3A, and the recovery of the respective and integral pharmacokinetics of lignans components. The integral AUC0-tn and CYP3A activities correlated well with ALT and AST. This study suggested that the pharmacokinetic regulating effects of hepatoprotective agent's on themselves and co-prescribed drugs should be of concern, and hepatic injury biomarkers may serve as good predictors.  相似文献   
49.
AIM: To explore whether the angiotensin Ⅱ (Ang Ⅱ) receptor 1 (AT1) antagonist, losartan could reduce activity and expression of matrix metalloproteinases (MMPs) in rat atherosclerotic plaques. METHODS: Male Wistar-Kyoto rats were ip injected a single dose of vitamin D3 600 kU·kg-1·month-1 and fed an atherogenic diet for 4 months to induce experimental atheroma. Then either placebo or losartan 50 mg·kg-1·d-1 was administered in rats for another 2 months. In vitro, the effect of losartan 0.1-10μmol/L on the expression of MMP-2 and MMP-9 was investigated in Ang II-stimulated rat peritoneal macrophages. The expression and activity of MMP-2 and MMP-9 were monitored by Western blot, RT-PCR, and SDS-PAGE zymography analysis. RESULTS: High levels of MMP-2 and MMP-9 were expressed in rat atherosclerotic lesions. Losartan significantly reduced the activity and expression of MMP-2 and MMP-9 compared with the placebo group (MMP-2, 5861±539 vs 8991±965, P<0.05; MMP-9, 10527±1002 vs 14623±2462, P<0.01). In  相似文献   
50.
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