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61.
中药有效成分治疗类风湿关节炎研究进展 总被引:3,自引:0,他引:3
中药治疗类风湿性关节炎(RA)有几千年的临床应用历史,积累了丰富的经验.近年来,国内外针对中药复方和单味药的抗RA作用开展了大量的实验研究工作,很多中药的活性成分(组分)和作用机制得到初步阐明,开发出青藤碱注射液、雷公藤多苷片和白芍总苷片等新型RA治疗药物.本文对中药有效成分在治疗RA方面的研究进展进行综述. 相似文献
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Dragon's blood may have radioprotective effects in radiation-induced rat brain injury 总被引:2,自引:0,他引:2
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Qiang Yu Weiqi Dai Jie Ji Liwei Wu Jiao Feng Jingjing Li Yuanyuan Zheng Yan Li Ziqi Cheng Jie Zhang Jianye Wu Xuanfu Xu Chuanyong Guo 《Journal of cellular and molecular medicine》2022,26(10):3031
Aerobic glycolysis is a well‐known hallmark of hepatocellular carcinoma (HCC). Hence, targeting the key enzymes of this pathway is considered a novel approach to HCC treatment. The effects of sodium butyrate (NaBu), a sodium salt of the short‐chain fatty acid butyrate, on aerobic glycolysis in HCC cells and the underlying mechanism are unknown. In the present study, data obtained from cell lines with mouse xenograft model revealed that NaBu inhibited aerobic glycolysis in the HCC cells in vivo and in vitro. NaBu induced apoptosis while inhibiting the proliferation of the HCC cells in vivo and in vitro. Furthermore, the compound inhibited the release of lactate and glucose consumption in the HCC cells in vitro and inhibited the production of lactate in vivo. The modulatory effects of NaBu on glycolysis, proliferation and apoptosis were related to its modulation of hexokinase 2 (HK2). NaBu downregulated HK2 expression via c‐myc signalling. The upregulation of glycolysis in the HCC cells induced by sorafenib was impeded by NaBu, thereby enhancing the anti‐HCC effect of sorafenib in vitro and in vivo. Thus, NaBu inhibits the expression of HK2 to downregulate aerobic glycolysis and the proliferation of HCC cells and induces their apoptosis via the c‐myc pathway. 相似文献
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Han Dai Lauren Kustigian David Carney April Case Thomas Considine Basil P. Hubbard Robert B. Perni Thomas V. Riera Bruce Szczepankiewicz George P. Vlasuk Ross L. Stein 《The Journal of biological chemistry》2010,285(43):32695-32703
SIRT1 is a protein deacetylase that has emerged as a therapeutic target for the development of activators to treat diseases of aging. SIRT1-activating compounds (STACs) have been developed that produce biological effects consistent with direct SIRT1 activation. At the molecular level, the mechanism by which STACs activate SIRT1 remains elusive. In the studies reported herein, the mechanism of SIRT1 activation is examined using representative compounds chosen from a collection of STACs. These studies reveal that activation of SIRT1 by STACs is strongly dependent on structural features of the peptide substrate. Significantly, and in contrast to studies reporting that peptides must bear a fluorophore for their deacetylation to be accelerated, we find that some STACs can accelerate the SIRT1-catalyzed deacetylation of specific unlabeled peptides composed only of natural amino acids. These results, together with others of this study, are at odds with a recent claim that complex formation between STACs and fluorophore-labeled peptides plays a role in the activation of SIRT1 (Pacholec, M., Chrunyk, B., Cunningham, D., Flynn, D., Griffith, D., Griffor, M., Loulakis, P., Pabst, B., Qiu, X., Stockman, B., Thanabal, V., Varghese, A., Ward, J., Withka, J., and Ahn, K. (2010) J. Biol. Chem. 285, 8340–8351). Rather, the data suggest that STACs interact directly with SIRT1 and activate SIRT1-catalyzed deacetylation through an allosteric mechanism. 相似文献
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Henry Annan Amber‐Leigh Golding Yinping Zhao Zhongmin Dong 《Ecology and evolution》2012,2(9):2285-2290
The H2 is an obligate by-product of N-fixation. Recycling of H2 through uptake hydrogenase (Hup) inside the root nodules of leguminous plants is often considered an advantage for plants. However, many of the rhizobium-legume symbioses found in nature, especially those used in agriculture are shown to be Hup−, with the plants releasing H2 produced by nitrogenase activity from root nodules into the surrounding rhizosphere. Recent studies have suggested that, H2 induces plant-growth-promoting rhizobacteria, which may explain the widespread of Hup− symbioses in spite of the low energy efficiency of such associations. Wild legumes grown in Nova Scotia, Canada, were surveyed to determine if any plant-growth characteristics could give an indication of Hup choice in leguminous plants. Out of the plants sampled, two legumes, Securigera varia and Vicia cracca, showed Hup+ associations. Securigera varia exhibited robust root structure as compared with the other plants surveyed. Data from the literature and the results from this study suggested that plants with established root systems are more likely to form the energy-efficient Hup+ symbiotic relationships with rhizobia. Conversely, Hup− associations could be beneficial to leguminous plants due to H2-oxidizing plant-growth-promoting rhizobacteria that allow plants to compete successfully, early in the growing season. However, some nodules from V. cracca tested Hup+, while others were Hup−. This was similar to that observed in Glycine max and Pisum sativum, giving reason to believe that Hup choice might be affected by various internal and environmental factors. 相似文献
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