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Xiong N Xiong J Khare G Chen C Huang J Zhao Y Zhang Z Qiao X Feng Y Reesaul H Zhang Y Sun S Lin Z Wang T 《PloS one》2011,6(6):e20677
3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone), an effective free radical scavenger, provides neuroprotection in stroke models and patients. In this study, we investigated its neuroprotective effects in a chronic rotenone rat model for Parkinson's disease. Here we showed that a five-week treatment with edaravone abolished rotenone's activity to induce catalepsy, damage mitochondria and degenerate dopamine neurons in the midbrain of rotenone-treated rats. This abolishment was attributable at least partly to edaravone's inhibition of rotenone-induced reactive oxygen species production or apoptotic promoter Bax expression and its up-regulation of the vesicular monoamine transporter 2 (VMAT2) expression. Collectively, edaravone may provide novel clinical therapeutics for PD. 相似文献
43.
Hu S Ni W Sai W Zhang H Cao X Qiao J Sheng J Guo F Chen C 《Biotechnology letters》2011,33(10):1949-1953
Myostatin is a negative regulator of skeletal muscle growth. Myostatin dysfunction therefore offers a strategy for promoting
animal muscle growth in livestock production. Knockdown of myostatin was achieved by combining RNA interference and the Sleeping
Beauty (SB) transposon system in sheep cells. Four targeting sites of sheep myostatin were designed and measured for myostatin
silencing in sheep fetal fibroblasts by real-time PCR. The sh3 construct induced significant decrease of myostatin gene expression
by 90% (P < 0.05). Myostatin silencing induced by SB-mediated sh3 was further tested in stably transfected cells. SB transposition
increased the integration frequency of genes into sheep genomes and mediated a more efficient myostatin knockdown than random
integration of sh3. We suggest that SB-mediated shRNA provides a novel potential tool for gene knockdown in the donor cells
of animal cloning. 相似文献
44.
Zhenfei Guo Meiyan Huang Shaoyun Lu Zhao Yaqing Qiao Zhong 《Acta Physiologiae Plantarum》2007,29(1):39-46
The responses of antioxidative system and photosystem II photochemistry of rice (Oryza sativa L.) to paraquat induced oxidative stress were investigated in a chilling-tolerant cultivar Xiangnuo no. 1, and a chilling-susceptible
cultivar, IR-50. Electrolyte leakage and malondialdehyde (MDA) content of Xiangnuo no. 1 were little affected by paraquat,
but they increased in IR-50. After paraquat treatment, superoxide dismutase (SOD) activity remained high in Xiangnuo no. 1,
while it declined in IR-50. Activities of catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) declined
with oxidative stress in both cultivars, but Xiangnuo no. 1 had higher GR activity than IR-50. Under paraquat induced oxidative
stress, ascorbic acid (AsA) and reduced glutathione (GSH) concentrations remained high in Xiangnuo no. 1, but decreased in
IR-50. The results indicated that higher activities of SOD and GR and higher contents of AsA and GSH in Xiangnuo no. 1 under
paraquat induced oxidative stress were associated with its tolerance to paraquat, while paraquat induced damage to IR-50 was
related to decreased activities of SOD, APX and GR and contents of AsA and GSH. F
v/F
m, Φ
PSII, and qP remained high in Xiangnuo no. 1, while they decreased greatly in IR-50 under paraquat induced oxidative stress. 相似文献
45.
Reversal of multidrug resistance of vincristine-resistant gastric adenocarcinoma cells through up-regulation of DARPP-32 总被引:1,自引:0,他引:1
Hong L Wang J Han Y Zhao Y Gao J Wang J Han Y Zhang X Yan L Zhou X Qiao T Chen Z Fan D 《Cell biology international》2007,31(9):1010-1015
Here we investigated the roles of DARPP-32 in multidrug resistance (MDR) of gastric cancer cells and the possible underlying mechanisms. We constructed the eukaryotic expression vector of DARPP-32 and transfected it into human vincristine-resistant gastric adenocarcinoma cell line SGC7901/VCR. Up-regulation of DARPP-32 could significantly enhance the sensitivity of SGC7901/VCR cells towards vincristine, adriamycin, 5-fluorouracil and cisplatin, and could decrease the capacity of cells to efflux adriamycin. What's more, the results of subrenal capsule assay confirmed that DARPP-32 might play a certain role in MDR of gastric cancer. DARPP-32 could significantly down-regulate the expression of P-gp and zinc ribbon domain-containing 1 (ZNRD1), but not alter the expression of multidrug resistance-associated protein (MRP) or the glutathione S-transferase (GST). DARPP-32 could also significantly decrease the anti-apoptotic activity of SGC7901/VCR cells. Further study of the biological functions of DARPP-32 might be helpful for understanding the mechanisms of MDR in gastric cancer. 相似文献
46.
Ma W Belisle SE Mosier D Li X Stigger-Rosser E Liu Q Qiao C Elder J Webby R Katze MG Richt JA 《Journal of virology》2011,85(22):11626-11637
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48.
植物通过内源激素或环境信号调控叶腋内腋芽的形成和发育,从而控制其分枝特性。独脚金内酯(strigolactones,SLs),一种产生于植物根部的类胡萝卜素衍生物,具有刺激寄生植物种子的萌发和促进丛枝菌根真菌菌丝分枝的作用,最近的研究表明,它还可以沿茎干向上运输,与生长素和细胞分裂素一起直接或间接抑制植物分枝,目前已经作为一种新的植物激素受到广泛认可。本文综述了独脚金内酯的结构、合成途径和生物活性,以及调控植物分枝的分子机理,并展望了其在抑制杂草或新型除草剂的研发、促进植物和有益真菌的共生,以及调控作物的分枝和株型等方面的应用前景。 相似文献
49.
Combinatorial Screening and Intracellular Antiviral Activity of Hairpin Ribozymes Directed against Hepatitis B Virus 总被引:14,自引:0,他引:14 下载免费PDF全文
A combinatorial screening method has been used to identify hairpin ribozymes that inhibit hepatitis B virus (HBV) replication in transfected human hepatocellular carcinoma (HCC) cells. A hairpin ribozyme library (5 x 10(5) variants) containing a randomized substrate-binding domain was used to identify accessible target sites within 3.3 kb of full-length in vitro-transcribed HBV pregenomic RNA. Forty potential target sites were found within the HBV pregenomic RNA, and 17 sites conserved in all four subtypes of HBV were chosen for intracellular inhibition experiments. Polymerase II and III promoter expression constructs for corresponding hairpin ribozymes were generated and cotransfected into HCC cells together with a replication-competent dimer of HBV DNA. Four ribozymes inhibited HBV replication by 80, 69, 66, and 49%, respectively, while catalytically inactive mutant forms of these ribozymes affected HBV replication by 36, 28, 0, and 0%. These findings indicate that the inhibitory effects on HBV replication were largely mediated by the catalytic activity of the ribozymes. In conclusion, we have identified catalytically active RNAs by combinatorial screening that mediate intracellular antiviral effects on HBV. 相似文献
50.