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121.
Yiqun Tang Minhui WangXiaoyong Le Jianing MengLu Huang Peng YuJia Chen Ping Wu 《Phytomedicine》2011,18(12):1024-1030
Myocardial hypertrophy has been linked to the development of a variety of cardiovascular diseases, and is a risk factor for myocardial ischemia, arrhythmias, and sudden cardiac death. The objective of the present study was to evaluate the cardioprotective effects of Danshensu (DSS), a water-soluble active component of Danshen, on cardiac hypertrophy in rats. We are the first to report that DSS reversed Cx43 down-regulation in ventricular tissue. Cardiomyopathy in rats was produced using isoproterenol (Iso) treatment (2.5 mg/kg/d, s.c.) for seven days. DSS (3 and 10 mg/kg/d, i.p.) and Valsartan (Val) (10 mg/kg, i.g.) were administered on days 4-7 of Iso-treatment. Heart weight index, hemodynamic parameters, and ECG II parameters were monitored and recorded; protein expression of left ventricular connexin 43 (Cx43) and the activity of the redox system were assayed, and arrhythmias were produced using a coronary ligation/reperfusion procedure. The results demonstrated that DSS treatment significantly decreased heart weight/body weight (HW/BW) and left ventricular weight/body weight (LVW/BW) ratios. The protective role of DSS against Iso-induced myocardial hypertrophy was further confirmed using ECG. The incidences of ventricular tachycardia and ventricular fibrillation (VT, VF) and arrhythmic scores were higher in the model group and were suppressed by DSS. DSS decreased the serum and myocardium levels of creatine kinase, lactate dehydrogenase, and malondialdehyde (CK, LDH, and MDA) and increased serum activity of superoxide dismutase (SOD) in a dose-dependent manner. Cx43 expression in the left ventricle was down-regulated, and there was significant oxidative stress in this model of cardiomyopathy. DSS reversed the down-regulated Cx43 protein levels and showed potent anti-oxidative activities and cellular protection. These data demonstrate that DSS can prevent cardiac I/R injury and improve cardiac function in a rat model of hypertrophy, the effects partially resulting from antioxidants and the protection from Cx43 expression. 相似文献
122.
Po Yee ChiuSze Man Wong Hoi Yan LeungPou Kuan Leong Na ChenLimin Zhou Zhong ZuoPhilip Y. Lam Kam Ming Ko 《Phytomedicine》2011,18(11):916-925
Danshen-Gegen (DG) decoction, an herbal formulation comprising Radix Salvia Miltiorrhiza and Radix Puerariae Lobatae, is prescribed for the treatment of coronary heart disease in Chinese medicine. Experimental and clinical studies have demonstrated that DG decoction can reduce the extent of atherosclerosis. In the present study, using an ex vivo rat model of myocardial ischemia/reperfusion (I/R) injury, we investigated the myocardial preconditioning effect of an aqueous DG extract prepared from an optimized weight-to-weight ratio of Danshen and Gegen. Short-term treatment with DG extract at a daily dose of 1 g/kg and 2 g/kg for 3 days protected against myocardial I/R injury in rats. The cardioprotection afforded by DG pretreatment was paralleled by enhancements in mitochondrial antioxidant status and membrane structural integrity, as well as a decrease in the sensitivity of mitochondria to Ca2+-stimulated permeability transition in vitro, particularly under I/R conditions. Short-term treatment with the DG extract also enhanced the translocation of PKC? from the cytosol to mitochondria in rat myocardium, and this translocation was inhibited by α-tocopherol co-treatment with DG extract in rats. Short-term DG treatment may precondition the myocardium via a redox-sensitive PKC?/mKATP pathway, with resultant inhibition of the mitochondrial permeability transition through the opening of mitochondrial KATP channels. Our results suggest that clinical studies examining the effectiveness of DG extract given prophylactically in affording protection against myocardial I/R injury would be warranted. 相似文献
123.
Łukasz Cieśla Dorota Staszek Michał Hajnos Teresa Kowalska Monika Waksmundzka‐Hajnos 《Phytochemical analysis : PCA》2011,22(1):59-65
Introduction – Plant‐derived free radical scavengers have become the subject of intensive scientific interest. Recently, the concept of coupling chromatographic fingerprints with biological fingerprinting analysis has gained much attention for the quality control of plant extracts. However, identification of free radical scavenging activity of each single compound in a complex mixture is a difficult task. Thin‐layer chromatography with post‐chromatographic derivatisation with the methanol solution of DPPH can be a valuable tool in such analyses. Objective – Development of chromatographic and free radical scavenging fingerprints of nineteen Salvia species grown and cultivated in Poland. Methodology – Chromatography was performed on the silica gel layers with use of two eluents, one for the resolution of the less polar compounds, and the other one for the resolution of the medium and highly polar ones. The plates were sprayed with the vanillin–sulfuric acid reagent to produce chemical fingerprints, and with DPPH solution to generate free radical scavenging fingerprints. Results – With four Salvia species, it was revealed that their strong free radical scavenging properties are not only due to the presence of polar flavonoids and phenolic acids, but also due to the presence of several free radical scavengers in the less polar fraction. Because of the similarities in both the chromatographic and the free radical scavenging fingerprints, S. triloba can be introduced as a possible equivalent of the pharmacopoeial species, S. officinalis. Conclusion – Fingerprints developed in the experiments proved useful for the analysis of complex extracts of the different Salvia species. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
124.
丹参肉桂酰辅酶A还原酶基因克隆与生物信息学分析 总被引:3,自引:0,他引:3
分析丹参转录组数据库,获得一条新的肉桂酰辅酶A还原酶(cinnamoyl-CoA reductase,CCR)基因,命名为SmCCR-2(GenBank注册号为JF784010)。该基因包含一个长为966 bp的完整开放读码框,编码321个氨基酸残基。生物信息学分析显示,SmCCR-2编码的蛋白具有NWYCY基序,属于NABD_Rossmann超家族,相对分子量为35.80 kD;预测SmCCR-2为中性亲水的稳定蛋白,存在跨膜结构域。实时荧光定量PCR结果表明,SmCCR-2基因在丹参各组织都有表达,茎中表达量最高。其表达受到病原菌的影响,表明SmCCR-2基因可能与植物防御反应有关。 相似文献
125.
Abstract: The genus Salvia encompasses about 900 species distributed world-wide. It is characterized by the famous staminal lever mechanism of the flower which is one of the best known examples of a nototribic pollination mechanism. We hypothesize that structure and functioning of the staminal levers play a major role as key structures in speciation. To cope with the complex evolutionary processes involved, a number of different methodological approaches are needed. The present paper summarizes the literature referring to structural and functional diversity, breeding systems, systematics and evolution in Salvia. 相似文献
126.
127.
128.
荫生鼠尾草植物中的三萜类化学成分研究 总被引:3,自引:2,他引:1
从采自陕西省太白山的唇形科(Labiatae)鼠尾草属(Salvia Linn.)植物荫生鼠尾草(Salvia umbratica Hance)丙酮提取物中分离得到14个五环三萜类化合物,并用现代波谱技术(MS、1H NMR、13C NMR、DEPT)和化学方法进行结构鉴定.结果显示:14个化合物分别为β-香树脂醇(1)、α-香树脂醇(2)、2α,3α-二羟基齐墩果-12-烯-28-酸(3)、3-氧-乌苏-12-烯-28-酸(4)、2α,3β-二羟基齐墩果-12-烯-28-酸(5)、3β,19-二羟基齐墩果-12-烯-28-酸(6)、齐墩果酸(7)、2α,3β-二羟基乌苏-12-烯-28-酸(8)、3β-羟基-11α-甲氧基-齐墩果-12-烯(9)、3β-羟基-11α-甲氧基-乌苏-12-烯(10)、3β,11α-二羟基-齐墩果-12-烯(11)、3β,11α-二羟基-乌苏-12-烯(12)、乌苏酸(13)、3β-羟基齐墩果-10,12-二烯(14).实验结果表明五环三萜类化合物是该植物中的主要成分. 相似文献
129.
用甲醇作提取溶剂,在回流条件下考察了从丹参药材中提取丹参酮类有效成分的过程中,隐丹参酮、丹参酮I及丹参酮IIA等三种丹参酮的热降解行为。结果表明,回流提取过程中所考察的三种丹参酮均发生严重的热降解,降解速率:丹参酮IIA>丹参酮I>隐丹参酮,其热降解均具有零级反应动力学特征;同时,回流提取过程中丹参酮的热降解是在丹参酮共萃物存在下发生的。 相似文献
130.
Lima CF Valentao PC Andrade PB Seabra RM Fernandes-Ferreira M Pereira-Wilson C 《Chemico-biological interactions》2007,167(2):107-115
Common sage (Salvia officinalis L., Lamiaceae) is an aromatic and medicinal plant well known for its antioxidant properties. Some in vivo studies have shown the biological antioxidant effects of sage. However, the intracellular antioxidant mechanisms of action are still poorly understood. In this study, we evaluated the cytoprotective effects of two sage extracts (a water and a methanolic extract) against tert-butyl hydroperoxide (t-BHP)-induced toxicity in HepG2 cells. The most abundant phenolic compounds present in the extracts were rosmarinic acid and luteolin-7-glucoside. Both extracts, when co-incubated with the toxicant, protected significantly HepG2 cells against cell death. The methanolic extract, with a higher content of phenolic compounds than the water extract, conferred better protection in this in vitro model of oxidative stress with liver cells. Both extracts, tested in a concentration that protects 80% against cell death (IC(80)), significantly prevented t-BHP-induced lipid peroxidation and GSH depletion, but not DNA damage assessed by the comet assay. The ability of sage extracts to reduce t-BHP-induced GSH depletion by 62% was probably the most relevant contributor to the observed cytoprotection. A good correlation between the above cellular effects of sage and the effects of their main phenolic compounds was found. When incubated alone for 5h, sage extracts induced an increase in basal GSH levels of HepG2 cells, which indicates an improvement of the antioxidant potential of the cells. Compounds present in sage extracts other than phenolics may also contribute to this latter effect. Based in these results, it would be of interest to investigate whether sage has protective effects in suitable in vivo models of liver diseases, where it is known that oxidative stress is involved. 相似文献