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21.
槲皮素对系膜细胞增殖、凋亡及细胞外基质的影响   总被引:1,自引:0,他引:1  
申兵冰  张杰  何俊 《四川医学》2006,27(7):663-665
目的观察槲皮素对系膜细胞增殖、凋亡及细胞外基质的影响。方法用MTT法检测细胞增殖.流式细胞仪检测细胞周期及凋亡,ELISA法测量纤雏连接蛋白(FN),Ⅳ型胶原(ColⅣ)在培养上清中的含量。结果在5-20μmol/L浓度范围内槲皮素能时间、剂量依赖性地抑制系膜细胞增殖,可使G0—G1期细胞增多,S期细胞减少,而较高浓度的槲皮素能剂量依赖性诱导系膜细胞的凋亡。同时槲皮素能减少系膜细胞在AngⅡ诱导下的FN和Col-Ⅳ的分泌。结论槲皮素可显著抑制系膜细胞增殖,使系膜细胞阻滞于G0-G1期;并且高浓度槲皮素有诱导系膜细胞凋亡的作用,并能减少系膜细胞在AngⅡ诱导下的细胞外基质的分泌。  相似文献   
22.
油菜花粉中槲皮素和山柰素总含量的HPLC法测定   总被引:7,自引:0,他引:7  
目的:建立油菜花粉中槲皮素与山柰素总含量的HPLC法的测定方法.方法:以HPLC法定量分析山柰素、槲皮素总含量.色谱条件:色谱柱:Eclipse XDB-C8(150mm×4.6mm,5μm),流动相:甲醇-0.4%磷酸溶液(50:50),检测波长:360nm,流速:1.0mL·min-1,进样量:10μL,以峰面积外标法定量.结果:山柰素与槲皮素的峰与其他色谱峰分离良好,槲皮素在进样量(0.029~0.73μg)、山柰素在进样量(0.053~1.315μg)的范围内,线性关系良好,回归方程分别为:槲皮素线性方程y=3 727.7X-6.0,相关系数r=0.999 9;山柰素线性方程Y=3 932.6X 3.5,相关系数r=0.999 9.槲皮素平均回收率为99.6%,RSD=1.6%,山柰素平均回收率为99.6%,RSD=2.0%.结论:本方法结果准确,重现性好,可以作为油菜花粉中槲皮素和山柰素总含量的定量分析方法.  相似文献   
23.
周江泉  汤致强 《中国药学》2005,14(4):231-236
目的体外代谢研究槲皮素对大鼠肝CYP1A2,CYP2E1,和CYP3A2活性的影响。研究其抑制强度及抑制机制。方法QU与底物共同温孵,HPLC检测底物特定的代谢产物生成量的变化反映对应亚酶的活性变化。比较槲皮素与酮康唑,红霉素在相同浓度下对CYP3A2的抑制能力强弱。不同浓度槲皮素对CYP3A2和CYP2E1底物代谢产物生成双倒数直线的影响初步分析槲皮素可能的抑制机制。结果各HPLC检测方法线性相关系数均>0.9991,RSD均<8.4%,回收率91.1%-107.6%。槲皮素在体外0~8μmol·L-1诱导大鼠肝微粒体CYP1A2的活性达338.1%,并抑制CYP2E1(49.2%),和CYP3A2(60.3%)。槲皮素对CYP3A2的抑制能力在酮康唑和红霉素之间。槲皮素竞争性抑制CYP3A2右美沙芬N脱甲基反应,非竞争性抑制CYP2E1氯唑沙宗6羟化反应。结论槲皮素对多个CYP450亚酶有抑制作用,它是有效的CYP3A竞争性抑制剂。做为黄酮类植物雌激素,槲皮素有分子结构的优势亦有对CYP450酶调控能力而具有未来抗肿瘤药物研究的潜力。  相似文献   
24.
目的 探讨热应激预处理能够减少肝脏缺血再灌注损伤的机制,以期寻找减轻肝脏缺血再灌注损伤的有效措施。方法 建立大鼠肝脏缺血再灌注损伤模型。将42只大鼠随机分为6组:①正常对照组(N);②槲皮素组(Q):腹腔注射槲皮素(quercetin, 7mg·kg-1 );③肝脏缺血再灌注(ischemi areperfusion,I/R)组(I);④热应激预处理组(H+I):缺血再灌注前16h给予热应激预处理;⑤槲皮素+热应激预处理组(Q+H+I):缺血再灌注前16h先给予槲皮素腹腔注射(7mg·kg-1 )再给予热应激处理;⑥槲皮素+缺血组(Q+I):缺血再灌注前16h给予槲皮素腹腔注射(7mg·kg-1 )。观察以上各组大鼠在肝脏缺血再灌注6h后热休克蛋白70(Heatshockprotein70, HSP70 )的表达,血清谷丙转氨酶(ALT)、谷草转氨酶(AST)的活性及肝脏组织形态学改变。结果 大鼠肝脏HSP70表达由高到低依次为:H+I组、I组、Q+H+I组、I+Q组、Q组、N组;而检测血清ALT、AST含量由高到低依次为:Q+I组、I组、Q+H+I组、H+I组、Q组、N组;肝脏组织形态学的改变显示与上述血中ALT、AST含量变化相对应。结论 HSP70在经热应激预处理后减少肝脏缺血再灌注损伤的过程中起重要的作用。  相似文献   
25.
HPLC法测定栘衣中槲皮素的含量   总被引:1,自引:0,他引:1  
目的测定傣药栘衣中槲皮素的含量.方法采用高效液相色谱法,C18柱为固定相,甲醇-0.4%磷酸为流动相,梯度洗脱,360 nm为检测波长,柱温为30℃.结果槲皮素在0.586~11.72μg范围内,峰面积与其浓度呈良好线性关系(r=0.9999),平均回收率为99.52%,RSD=1.2%(n=3).结论该法简单、快速,重现性好.  相似文献   
26.
槲皮素抑制血管生成作用的实验研究   总被引:21,自引:1,他引:21  
目的 研究槲皮素 (Quercetin)对血管生成和培养的人脐静脉内皮细胞 (HUVEC)的影响。方法 采用生长因子 (血管内皮细胞生长因子VEGF、碱性成纤维细胞生长因子bFGF)诱导的鸡胚绒毛尿囊膜 (CAM)血管增生模型观察槲皮素对血管生成的影响 ;利用培养的HUVEC ,用MTT法观察槲皮素抑制内皮细胞增殖的作用 ;流式细胞仪观察槲皮素对HUVEC细胞周期的影响。结果 槲皮素 (0 1、0 0 5和 0 0 2 5mmol·L-1)能明显抑制VEGF诱导的CAM小血管生成 ;槲皮素 (0 1和 0 0 5mmol·L-1)能明显抑制bFGF诱导的CAM小血管生成 ;槲皮素 (2 4 0、12 0 μmol·L-1和 6 0 μmol·L-1)对内皮细胞增殖有抑制作用 ,抑制率分别为 6 7 0 %、5 8 1%和39 7% ;槲皮素 (2 4 0、12 0 μmol·L-1)能显著导致HUVEC的S、G2 期阻滞。结论 槲皮素能抑制VEGF和bFGF诱导的血管生成 ,且对内皮细胞增殖具有抑制作用。  相似文献   
27.
Background: Interstitial cystitis is characterized by over 6 months of chronic pain, pressure and discomfort felt in the lower pelvis or bladder. It is often relieved with voiding, along with daytime frequency and nocturia in the absence of a urinary tract infection. Interstitial cystitis occurs primarily in females including adolescents and its diagnosis is still one of exclusion. It is now recognized as a serious medical condition associated with significant disability. Objective: The aim of this paper was to review the pathogenesis and treatment of interstitial cystitis with emphasis on new pathogenetic trends and therapeutic modalities. Methods: About 713 mostly original papers were reviewed in Medline from 1990 to August. 2008. All authors independently reviewed the literature. Large, double-blind, placebo-controlled, clinical trials were few and the medical histories of the patients used varied considerably making conclusions difficult. Promising pilot trials turned out mostly negative on follow-up. Results: Increasing evidence of co-morbid diseases, neurogenic inflammation and the effect of stress are promising as new targets for pathophysiology. No new effective treatments have emerged. Oral pentosanpolysulfate, amitriptyline, hydroxyzine and quercetin, as well as intravesical heparin/bicarbonate/lidocaine solutions, are still used with variable success. Some pilot open-label trials presented encouraging findings. Conclusion: Interstitial cystitis contributes substantially to chronic pelvic pain and to poor quality of life. Oral or intravesical administration of solutions containing sodium hyaluronate, chondroitin sulfate and quercetin to both reduce bladder inflammation and ‘replenish’ the glycosaminoglycan layer should be tried. There is a clear need for therapeutic modalities. New potential translational research areas are suggested.  相似文献   
28.
Objective:To investigate the effects of quercetin on Hedgehog(Hh) signaling in chronic myeloid leukemia KBM7 cells.Methods:The KBM7 cells were treated with 50,100 and 200 μmol/L quercetin for48 h respectively.And then the trypan blue assay was used to examine the proliferative inhibition of quercetin.Apoptotic cells and cell cycle were measured by flow cytometry.The mRNA and protein expression were detected by quantitative real-time polymerase chain reaction(PCR) and Western blot,respectively.Results:Quercetin significantly inhibited KBM7 cell proliferation,induced cell apoptosis,and blocked cell cycle at G1 phase,which were in dose-dependent manners.The mRNA and protein expression of Smoothened and Gliomal(Gli1),the members of Hh pathway decreased after treatment with quercetin.The Bcl-2 and Cyclin D1,targets of Hh signaling,also decreased after treatment with quercetin,respectively.Quercetin also could increase p53 and Caspase-3 expression.Bcr-abl mRNA copies decreased,but no changes of phosphorylated Bcr-abl and Bcr-abl proteins were observed,after treatment with quercetin.Conclusion:Quercetin could inhibit Hh signaling and its downstream targets in the KBM7 cells.And it might be one of mechanisms of inducing apoptosis and inhibiting cell cycle by quercetin.  相似文献   
29.
Objective To study the ent-kaurane diterpenoids from Rabdosia rubescens. Methods The compounds were isolated by chromatographies and their structures were identified by spectral analyses. Results Four compounds were isolated, and they were identified as bisrubescensin E (1), 2α,3α,24-trihydroxyurs-12-en-28-oic acid (2), 2α,3α,24-trihydroxyurs-12,20-(30)-dien-28-oic acid (3), and 6,7-dihydroxycoumarin (4). Conclusion Compound 1 is a new asymmetric ent-kauranoid dimer. Compound 2 is isolated from the plant for the first time. Compounds 3 and 4 are isolated from the plants of Rabdosia (Bl.) Hassk for the first time.  相似文献   
30.
The main objective of our present work was to ascertain the efficacy of Drosophila melanogaster model for assessing antigenotoxic and antioxidant effects of dietary phytochemicals gallic acid (GA), quercetin (QC) and limonene (Lim) against urethane (URE), a genotoxic environmental carcinogen. Oregon-K (ORK) adult male flies were fed GA, QC and Lim in combination with URE (20?mM) in 10% sucrose for 72?h. Third instar larvae were fed instant medium containing the above phytochemicals and URE for 24?h. Sex-linked recessive lethal (SLRL) test and assays for estimating glutathione content (GSH), glutathione S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (MDA content) were performed. Adult feeding experiments demonstrated that co-treatment of flies with URE and the test phytochemicals has significantly decreased the frequencies of SLRL mutations in all the germ cell stages when compared to that with URE alone. Larval feeding experiments also showed a similar pattern. The above results correlate well with antioxidative potentials of the test agents where we observed the elevated enzymatic levels with a significant reduction in MDA level in Drosophila larvae. The results further suggest that the dietary phytochemicals have an antioxidant and antimutagenic property which can be assessed using D. melanogaster.  相似文献   
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