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21.
目的形成吉林省红、白车轴草异黄酮成分提取、分离、纯化方法,进行车轴草属植物异黄酮有效成分对比分析和研究。方法用乙醇提取车轴草属植物异黄酮有效成分,采用溶剂纯化法精制异黄酮,采用紫外分光光度法进行总异黄酮含量测定及提取工艺优化研究。结果车轴草属植物含有刺芒柄花素、鹰嘴豆芽素、染料木素及大豆苷元等,其中刺芒柄花素在车轴草属植物各部位含量丰富均衡,色谱分析结果稳定,可作为吉林省野生车轴草异黄酮成分分析标准品。结论吉林省野生红车轴草药用植物中所含异黄酮种类丰富,白车轴草中含有染料木素、刺芒柄花素等异黄酮成分,研究结果有望为我省长白山地区野生车轴草药用植物资源开发利用提供指导。 相似文献
22.
大豆异黄酮抑制去势兔动脉粥样硬化形成的实验研究 总被引:4,自引:0,他引:4
目的探讨大豆异黄酮对卵巢切除(OVX)兔血脂、内皮素-1(ET-1)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)水平及动脉粥样硬化斑块面积的影响.方法28只4月龄雌兔随机分为4组,每组7只.除A组行假手术外,余组均行OVX,并饲以胆固醇饮食,C组予大豆异黄酮,D组予雌二醇,12周后测定血脂、ET-1、TNF-α、IL-6及动脉粥样硬化斑块面积.结果与B组比较,C组、D组总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)均降低,C组高密度脂蛋白胆固醇(HDL-C)增高(P<0.0 5);C组、D组血浆ET-1、TNF-α、IL-6均降低(P<0.05),且动脉粥样硬化斑块面积占主动脉总面积的百分比明显降低(P<0.05).结论大豆异黄酮改善去势兔血脂,并降低ET-1、TNF-α、IL-6水平,可预防及减轻动脉粥样硬化. 相似文献
23.
T. Sathyapalan M. Aye A.S. Rigby N.J. Thatcher S.R. Dargham E.S. Kilpatrick S.L. Atkin 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2018,28(7):691-697
Background
Hormone replacement therapy may be beneficial for cardiovascular disease risk (CVR) in post-menopausal women. Soy isoflavones may act as selective estrogen receptor modulators. The aim of this study was to evaluate whether soy isoflavones had an effect on CVR markers.Methods
The expected 10-year risk of cardiovascular disease and mortality were calculated as a secondary endpoint from a double blind randomised parallel study involving 200 women (mean age 55 years, Caucasian, Hull, UK, 2012) in the early menopause who were randomised to 15 g soy protein with 66 mg isoflavone (SPI) or 15 g soy protein alone (depleted of all isoflavones; SP) given as a snack bar between meals daily for 6 months. Age, diabetes, smoking, blood pressure and lipid profiles were used to calculate CVR using the Framingham CVR engine.Results
SPI treatment resulted in a significant reduction in the metabolic parameters and systolic blood pressure compared to SP (p < 0.01). There were no changes in fasting lipid profile and diastolic blood pressure with either treatment. At 6 months, changes in these parameters with SPI treatment were reflected in a calculated 27% (p < 0.01) reduction in 10 year coronary heart disease risk, a 37% (p < 0.01) reduction in myocardial infarction risk, a 24% (p < 0.04) reduction in cardiovascular disease and 42% (p < 0.02) reduction in cardiovascular disease death risk.Conclusions
Supplementation with soy protein with isoflavones for 6 months significantly improved CVR markers and calculated CVR at 6 months during early menopause compared to soy protein without isoflavones.ISRCTN registry
ISRCTN34051237. 相似文献24.
目的 探究滇黄精Polygonatum kingianum传统炮制过程化学成分变化规律。方法 按照九蒸九晒法进行滇黄精炮制,应用分光光度法和HPLC测定炮制过程中总多糖、总皂苷、总多酚、总黄酮和游离氨基酸的含量。应用UPLC-MS/MS的广泛靶向代谢组学技术检测原料和炮制后的代谢产物。结果 随着炮制次数的增加,颜色逐渐加深,第3次蒸制后为深褐色,第4次至炮制结束缓慢转变为黑色。滇黄精原料具有麻味,第4蒸之后麻味消失,变为酸甜味。炮制过程中多糖和16种游离氨基酸含量降低,总皂苷、总黄酮和总多酚含量增加。广泛靶向代谢组学共检测到419个代谢物,氨基酸及其衍生物66个,脂质65个,酚酸类52个,黄酮类51个,有机酸42个,生物碱41个,核苷酸及其衍生物32个,甾体9个,木脂素和香豆素7个,异黄酮1个,萜类3个,其他类物质50个。结论 系统阐述了滇黄精九蒸九晒炮制过程中化学成分的变化,九蒸九晒对滇黄精中的化学成分影响较大,随着炮制时间的增加,氨基酸及其衍生物和生物碱类化合物的相对丰度降低,有机酸和酚酸类相对丰度增加等。该研究可为炮制滇黄精有效成分的筛选与质量评价提供参考,同时差异性成分的发现为研究滇黄精生熟饮片中差异性物质的分析提供新思路,对滇黄精的扩大开发利用有重要意义。 相似文献
25.
目的:观察大豆异黄酮对骨质疏松大鼠种植体周围骨以及骨结合强度的影响。方法:选用4月龄雌性SD大鼠40只,用随机区组的方法将其分为假手术组(SHAM,10只)、卵巢切除组(OVX,10只)、卵巢切除+高剂量大豆异黄酮组(OVX+SIH,10只)和卵巢切除+低剂量大豆异黄酮组(OVX+SIL,10只)共4组。术后8周所有实验动物双侧胫骨干骺端分别植入钛螺纹钉1颗,2个药物干预组使用不同剂量SI药物干预12周。所有实验动物取包含螺纹钉的骨组织块进行生物力学、组织形态定量学检查。结果:与OVX组相比,低剂量和高剂量SI均能有效增加种植体的骨结合(组织形态定量学检测),并且增加了种植体的最大脱出力,其中高剂量SI组的种植体稳定性与对照组无显著差别(生物力学检测)。结论:本研究结果说明大豆异黄酮有剂量依赖性地改善骨质疏松大鼠钛螺纹钉的骨结合强度的可能性,增强疏松状态下种植体的稳定性。 相似文献
26.
[目的]观察大豆异黄酮(SIF)对慢性肾损害大鼠营养状况的影响。[方法]先建立大鼠慢性肾损害模型,然后将其分为对照组、SIF小剂量组和SIF大剂量组,对照组予同等量花生油(溶媒)灌喂,SIF小剂量组予SIF6rag/(kg·d),SIF大剂量组予SIF 12mg/(kg·d),共观察42d。检测血总蛋白(TP)、白蛋白(ALB)、总胆固醇(CHOL)、尿素(BU)、肌酐(Ser)及24h尿蛋白定量。[结果]42d后与对照组比较,SIF治疗组血BU、Scr、24h尿蛋白、CHOL均显著降低(P〈0.05),而TP、ALB显著升高(P〈O.05),体重变化不明显。[结论]SIF对腺嘌呤诱导肾损害大鼠具有显著升高TP和ALB,降低CHOL并具有降低尿蛋白以及稳定肾功能的作用。 相似文献
27.
Occhiuto F Palumbo DR Samperi S Zangla G Pino A De Pasquale R Circosta C 《Phytotherapy research : PTR》2009,23(2):192-196
Oxidative stress-induced neuronal cell death has been implicated in different neurological disorders and neurodegenerative diseases such as Alzheimer's disease and Parkinson's. Using the Alzheimer's disease-associated hydrogen peroxide (H(2)O(2)), we investigated the neuroprotective efficacy of a natural mixture of phytoestrogenic isoflavones (genistein, daidzein, biochanin A and formononetin) from Trifolium pratense L. (Red clover) against oxidative stress-induced cell death in human cortical cell line HCN 1-A maintained in culture. Neuronal viability was determined by MTT or trypan blue test and neuronal integrity by morphological analysis.The results obtained indicate that exposure of HCN 1-A cell cultures to hydrogen peroxide resulted in a concentration-dependent decrease in neuron viability. Concentration of H(2)O(2) ranging from 50 to 200 microg/ml were toxic to these cultures. A 24-hour pretreatment with 0.5, 1 and 2 microg/ml isoflavones extract significantly increased cell survival as evidenced by MTT or trypan blue test and significantly prevented the morphological disruption caused by H(2)O(2) as shown by microscopical inspection, indicating that neurons treated with isoflavones were protected from the cell death induced by H(2)O(2) exposure. These findings imply that the neuroprotective effect of isoflavones extract is partly associated with its antioxidant activity. Further, results of these investigations indicate that although isoflavones extract exert a neuroprotective effect, it do not promoted cortical neuron process outgrowth. 相似文献
28.
Mechanisms of the growth inhibitory effects of the isoflavonoid biochanin A on LNCaP cells and xenografts 总被引:16,自引:0,他引:16
Rice L Samedi VG Medrano TA Sweeney CA Baker HV Stenstrom A Furman J Shiverick KT 《The Prostate》2002,52(3):201-212
BACKGROUND: Isoflavones inhibit the growth of some types of tumor cells, including prostate adenocarcinoma. This study used LNCaP cells and xenografts to investigate the mechanisms of the antiproliferative effects of biochanin A, a major isoflavone present in red clover but not soy-derived products. METHODS: LNCaP cells were exposed to varying doses of biochanin A to evaluate viability, DNA synthesis, and DNA fragmentation (TUNEL) analysis. Regulation of gene expression was determined by using Western immunoblotting and cDNA microarrays. Anti-tumorigenic effects were evaluated by using athymic mice with LNCaP flank tumors. RESULTS: Biochanin A induced a dose-dependent inhibition of proliferation and [(3)H]thymidine incorporation that correlated with increased DNA fragmentation, indicative of apoptosis. Western blot analyses of cell cycle regulatory proteins revealed that biochanin A significantly decreased expression of cyclin B and p21, whereas flow cytometry showed that cells were accumulating in the G(0)/G(1) phase. cDNA microarray analyses identified 29 down-regulated genes with six reduced below assay detection limits. Eleven genes were up-regulated, including 9 that were undetectable in controls. In mice with LNCaP xenografts, biochanin A significantly reduced tumor size and incidence. CONCLUSION: These results indicate that biochanin A inhibits prostate cancer cell growth through induction of cell cycle arrest and apoptosis. Biochanin A-regulated genes suggest multiple pathways of action. Biochanin A inhibits the incidence and growth of LNCaP xenograft tumors in athymic mice. 相似文献
29.
目的:探讨大豆异黄酮(Soy isoflavones,SI)对实验性高脂血症大鼠血脂水平及体内过氧化状态的影响。方法:用高脂饲料喂养Wistar大鼠,建立高脂血症大鼠模型,随后利用SI进行干预,实验9周腹主动脉取血,检测实验大鼠血清有关脂类代谢指标的变化情况。结果:高剂量SI显著抑制高脂饲料所致的血脂水平的升高(P〈0.01),促进apoAI氧化物升高具有拮抗作用,并可提高谷胱甘肽过氧化物酶(glutathione peroxi的合成,抑制apoB100的合成(P〈0.01),SI对实验性高脂血症大鼠体内脂质过dase,GSH-Px)、超氧化物歧化酶(superoxide dismutase,SOD)的抗氧化活性(P〈0.05~P〈0.01)。结论:SI对有明显高脂血症的作用,并能改善高脂所致体内异常的过氧化状态,保持肌体免遭过氧化损伤。 相似文献
30.
大豆异黄酮对绝经早期妇女围绝经期症状的改善效应观察 总被引:2,自引:0,他引:2
目的确定大豆异黄酮(soybean isoflavone,SI)改善由于雌激素缺失导致的围绝经期症状的生理效应有效剂量,并探讨其可能机制。方法90例45~60岁的绝经早期妇女,随机单盲分为SI84、126mg/(kgbw·d)两个剂量组和安慰剂对照组,每组30人接受追踪观察24w,每4w要求对象记录1w的潮热、出汗次数,做1次围绝经期症状评分(Kuppermanuscore),并在试验前、12w和24w时测定血清雌二醇(E2)、促卵泡生成素(FSH)和黄体生成素(LH)的浓度。结果在试验期间低、高剂量两组的潮热次数(%)分别为57.8±37.4和56.7±26.7和症状评分的下降率(%)分别为44.3±19.1和48.5±27.2,两组间无显著差异,而安慰剂组的潮热次数和症状评分下降率仅为(34.6±46.2)%和(27.8±15.5)%,显著低于前两组。血清E2、FSH和LH在试验各期各组间没有显著差异。结论大豆异黄酮84mg/d可以改善各种围绝经期症状,尤其是潮热、出汗症状,此效应与激素的调节关系不明显。 相似文献