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排序方式: 共有1154条查询结果,搜索用时 15 毫秒
91.
Xin Li Jian-Ning Wang Jun-Ming HuangXi-Kun Xiong Mei-Fen ChenChoon-Nam Ong Han-Ming ShenXing-Fen Yang 《Toxicology in vitro》2011,25(3):630-635
Chrysin exists widely in plants, honey and propolis. The anti-cancer property of chrysin has been demonstrated though the molecular mechanism is not clear. In this study, we found that pre-treatment with chrysin could promote the cell death induced by TRAIL according to the morphological changes and appearance of sub-G1 peak in four human cancer cell lines. In HCT-116 cells, the results of flow cytometry analysis showed that the percentage of sub-G1 reached (38.89 ± 3.78) % when pre-treatment of chrysin was used at 40 μM, but that was only (2.53 ± 0.10) % in the untreated group and (13.22 ± 0.20) % in TRAIL alone group. The differences between the combination and the untreated or TRAIL alone group were all significant (P < 0.05) and dose-dependent effect was obvious. Similar results were obtained in CNE1 cells. In the search of molecular mechanisms, we found that pre-treatment with chrysin could increase TRAIL-induced degradation of caspase 3, caspase 8, PARP proteins. Z-VAD-fmk, which is a pan-caspase inhibitor, could inhibit the apoptosis enhanced by the combination of chrysin and TRAIL. All data indicate that chrysin can enhance the apoptosis induced by TRAIL, and the apoptosis is caspase-dependent and related to the activation of caspase 8. 相似文献
92.
目的筛选大鼠痛风性关节炎(GA)生物标志物。方法采用改良的微晶尿酸钠和次黄嘌呤法制备大鼠急性GA模型,检测血尿酸、尿尿酸、24 h总尿量及滑膜组织病理形态学改变,采用RayBioBiotin Label-based Rat Antibody ArrayⅠ筛选差异表达蛋白。结果急性GA模型建立成功,发现GA中14个差异表达蛋白,其中9个细胞因子首见于GA,差异最明显2个蛋白为TRAIL与Neuropilin-2。结论 TRAIL与Neuropilin-2为GA生物标志物,为临床诊断与防治提供新靶点。 相似文献
93.
TNF-related apoptosis-inducing ligand (TRAIL) is a promising agent for management of cancer because of its selective cytotoxicity to cancer cells. However, some cancer cells have resistance to TRAIL. Accordingly, novel treatment strategies are required to overcome TRAIL resistance. Here, we examined the synergistic apoptotic effect of apigenin in combination with TRAIL in Huh-7 cells. We found that combined treatment of TRAIL and apigenin markedly inhibited Huh-7 cell growth compared to either agent alone by inducing apoptosis. Combined treatment with apigenin and TRAIL induced chromatin condensation and the cleavage of poly (ADP-ribose) polymerase (PARP). In addition, enhanced apoptosis by TRAIL/apigenin combination was quantified by annexin V/PI flow cytometry analysis. Western blot analysis suggested that apigenin sensitizes cells to TRAIL-induced apoptosis by activating both intrinsic and extrinsic apoptotic pathway-related caspases. The augmented apoptotic effect by TRAIL/apigenin combination was accompanied by triggering mitochondria-dependent signaling pathway, as indicated by Bax/Bcl-2 ratio up-regulation. Our results demonstrate that combination of TRAIL and apigenin facilitates apoptosis in Huh-7 cells. 相似文献
94.
目的 探讨高血糖对小鼠卵母细胞Ca2+振荡和卵泡颗粒细胞肿瘤坏死因子相关凋亡诱导配体(TRAIL)表达的影响.方法 出生后20d ICR雌鼠,用链脲酶素建立急性高血糖模型;高血糖模型雌鼠及正常雌鼠注射10IU/只孕马血清促性腺激素(PMSG)和人绒毛膜促性腺激素(hCG)超排卵,注射hCG后0h、2h、6h和10h取生发泡(GV)期卵母细胞,双光子激光扫描共焦显微镜检测GV期卵母细胞的Ca2+振荡;hCG注射后6h、10h取卵丘-卵母细胞复合体(COC),利用免疫荧光、Western blotting检测TRAIL的表达.结果 1.高血糖组卵母细胞Ca2+振荡频率高于正常对照组,于hCG注射后2h、6h差异显著(P<0.05);2.免疫荧光、Western blotting蛋白半定量检测显示,高血糖组颗粒细胞TRAIL表达量高于正常对照组,于hCG注射后6h、10h差异有显著性(P<0.05).结论 高血糖加快小鼠未成熟卵母细胞Ca2+振荡的频率;高血糖促进小鼠卵泡颗粒细胞TRAIL的表达. 相似文献
95.
5-azacytidine, a chemotherapeutic drug, induces TRAIL-mediated apoptosis in mouse thymocytes in vivo
Tomoaki TochitaniHiroyuki Kanemitsu Hirofumi YamauchiKazuyuki Uchida Hiroyuki Nakayama 《Experimental and toxicologic pathology》2011,63(3):237-242
5-azacytidine (5AzC) is a cytidine analogue with two main effects on cellular conditions; DNA damage, resulting in apoptosis, and DNA hypomethylation, restoring normal growth control and differentiation. However, the molecular mechanism of 5AzC-induced apoptosis is not fully understood. The aim of the present study is to clarify this mechanism in mouse thymocytes in vivo. Ten-week-old, male C57BL/6J mice were injected with 5AzC (100 mg/kg) intraperitoneally, and thymuses were examined for apoptotic changes. In the 5AzC-treated thymus, increases of TUNEL-positive thymocytes and cleaved caspase-3 protein, both biochemical features of apoptosis, were detected. 5AzC-induced apoptosis was observed even in the thymuses of mice deficient in p53, a critical factor in the intrinsic apoptotic pathway, and mice with mutated Fas, a death receptor. Furthermore, levels of p53 and Fas proteins were unchanged in the thymus following 5AzC-treatment in wild-type mice. In the 5AzC-treated thymus, the level of cleaved caspase-8 protein, an initiator of the extrinsic apoptotic pathway, increased with the cleavage of its target protein, Bid. Moreover, the level of TRAIL protein, which induces apoptosis through the cleavage of caspase-8, robustly increased in the thymus treated with 5AzC. In conclusion, the 5AzC-induced apoptosis of thymocytes in vivo is implemented through the extrinsic pathway with the activation of TRAIL. 相似文献
96.
多重调控病毒.基因载体的构建及其体外抗肿瘤活性 总被引:1,自引:1,他引:0
目的 构建一种新型的病毒.基因治疗载体.方法 通过克隆技术将人肿瘤坏死因子相关凋亡诱导配体(TRAIL)基因插入质粒载体pBHGE3的E3区,得到由主要晚期启动子(MLP)调控的腺病毒质粒pPE3-hTRAIL,再通过与质粒pSGS00在293细胞中进行位点特异性重组得到E1A、E1B基因分别受hTERT启动子与HRE启动子双重调控的重组增殖型腺病毒,用TCID50方法测定病毒滴度.通过增殖实验观察重组病毒的选择性增殖能力.利用酶联免疫吸附试验(ELISA)检测人TRAIL基因的表达.并进行噻唑蓝(MTT)比色法实验检测其杀伤肿瘤细胞的能力.结果 CNHK500-hTRAIL的病毒滴度为2.39×1010pfu/ml,增殖实验结果证实CNHK500-hTRAIL可以选择性地在端粒酶阳性的人肺癌细胞A549中增殖,其所携带的人TRAIL基因在A549中的表达量(183.12μg/L)明显高于携带该基因的非增殖型腺病毒载体Ad-hTRAIL(24.53μg/L,P<0.01).MTr显示CNHK500-hTRAIL对A549的杀伤能力明显高于携带该基因的非增殖型腺病毒载体Ad-hTRAIL,其半数抑制MOI值分别为17.825、0.197(P<0.01).结论 CNHKS00一hTRAIL是一种具备治疗肺癌潜力的新型病毒-基因治疗系统. 相似文献
97.
Gassler N Roth W Funke B Schneider A Herzog F Tischendorf JJ Grund K Penzel R Bravo IG Mariadason J Ehemann V Sykora J Haas TL Walczak H Ganten T Zentgraf H Erb P Alonso A Autschbach F Schirmacher P Knüchel R Kopitz J 《Gastroenterology》2007,133(2):587-598
BACKGROUND AND AIMS: The constant renewal of enterocytes along the crypt-villus axis (CVA) of human small intestine is due to cell-inherent changes resulting in the apoptotic cell death of senescent enterocytes. The aim of the present study was to examine underlying molecular mechanisms of the cell death at the villus tip. METHODS: Characterization of human acyl-coenzyme A (CoA) synthetase 5 (ACSL5) was performed by cloning, recombinant protein expression, biochemical approaches, and several functional and in situ analyses. RESULTS: Our data show that different amounts of acyl-CoA synthetase 5-full length (ACSL5-fl) and a so far unknown splice variant lacking exon 20 (ACSL5-Delta 20) are found in human enterocytes. In contrast with the splice variant ACSL5-Delta 20, recombinant and purified ACSL5-fl protein is active at a highly alkaline pH. Over expression of ACSL5-fl protein is associated with a decrease of the anti-apoptotic FLIP protein in a ceramide-dependent manner and an increased cell-surface expression of the death receptor TRAIL-R1. Expression analyses revealed that the ACSL5-fl/ACSL5-Delta 20 ratio increases along the CVA, thereby sensitizing ACSL5-fl-dominated cells at the villus tip to the death ligand TRAIL, which is corroborated by functional studies with human small intestinal mucosal samples and an immortalized human small intestinal cell line. CONCLUSIONS: Our results suggest an ACSL5-dependent regulatory mechanism that contributes to the cellular renewal along the CVA in human small intestine. Deregulation of the ACSL5-fl/ACSL5-Delta 20 homeostasis in the maturation and shedding of cells along the CVA might also be of relevance for the development of intestinal neoplasia. 相似文献
98.
Insulin-dependent diabetes mellitus (IDDM) is an organ-specific autoimmune disorder triggered by autoreactive T cells directed
to pancreas beta-cell antigens. In this disorder, more than 90% of beta cells are destroyed. Cell death may be mediated via
soluble or membrane-bound cell death ligands. One of these ligands may be tumour necrosis factor (TNF)-related apoptosis-inducing
ligand (TRAIL), a member of the TNF-α superfamily. In the present study, we examined whether TRAIL had cytotoxic effects on
adult rat pancreas beta cell cultures and INS1-E rat insulinoma cell line cultures or not. In this study, cell destruction
models were built with TRAIL concentrations of 10, 100 and 1000 ng. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide
(MTT) test was used for evaluating cell viability. It was detected that cell cultures with TRAIL added showed no differences
statistically when compared with control cultures containing no toxic additions. These results showed that TRAIL did not have
significant cytotoxic effects on pancreas beta cell culture and INS-1E rat insulinoma cell line cultures. Detection of the
expression of TRAIL receptors and natural apoptosis inhibitor proteins will be favourable to investigate the resistance mechanisms
to TRAIL-induced cell death in this cell culture system. 相似文献
99.
Olaf Hoffmann Frauke Zipp Joerg R. Weber 《Journal of molecular medicine (Berlin, Germany)》2009,87(8):753-763
In a wide variety of acute and chronic central nervous system (CNS) disorders, inflammatory processes contribute to the damage
of brain cells and progression of the disease. Along with other regulatory cytokines, tumour necrosis factor-related apoptosis-inducing
ligand (TRAIL) is involved in the pathology of multiple sclerosis (MS) and murine experimental autoimmune encephalomyelitis
(EAE), bacterial meningitis (BM), HIV encephalitis (HIVE), stroke and Alzheimer's disease (AD). In these conditions, TRAIL
is released within the brain mainly by activated microglia and leukocytes infiltrating from the blood stream. TRAIL promotes
apoptosis of parenchymal cells in MS/EAE, HIVE, AD and stroke through interaction with TRAIL death receptors expressed on
these cells. Frequently, cells in the diseased brain display increased susceptibility to apoptosis induction by TRAIL due
to upregulation of death receptors and downregulation of decoy receptors. On the other hand, TRAIL inhibits the proliferation
of encephalitogenic T cells in EAE, and it is involved in the clearance of infected brain macrophages in HIVE and of activated
neutrophils in BM by interaction with their death receptors. Especially in BM, the ability of TRAIL to limit an acute granulocyte-driven
inflammation carries significant neuroprotective potential. Given the diversity of beneficial and harmful effects in the immune
and nervous system, TRAIL is a double-edged sword in diseases involving CNS inflammation. 相似文献
100.
Elena Riboldi Roberta Daniele Marco A. Cassatella Silvano Sozzani Daniela Bosisio 《Immunobiology》2009,214(9-10):868
Plasmacytoid dendritic cells (PDC) are a functionally distinct lineage of dendritic cells characterized by the release of large amounts of type I interferon (IFN I). IFN I release is efficiently triggered by viral infection and modulates several aspects of immune reactions including the activation of cytotoxic mechanisms finalized to the elimination of infected cells. In this study, we report that TLR7 and TLR9 ligands can induce the secretion of biologically active TNF-related apoptosis-inducing ligand (TRAIL) by PDC. Accordingly, PDC supernatant is endowed with TRAIL-mediated cytotoxic activity when tested on a TRAIL-sensitive Jurkat cell line. TRAIL production is only partially dependent on the autocrine production of IFN I as documented by the use of a blocking anti-IFNRA antibody and the stimulation with exogenous IFN I. Importantly, both TRAIL secretion and cytotoxic activity of PDC supernatants are completely abolished by BDCA2 ligation. These results provide further insights into the biological role of BDCA-2 and document a negative regulatory pathway of PDC cytotoxic activity that may be relevant in pathological situations such as tumors and autoimmune diseases. 相似文献