• 【Ox草叶中的类黄酮和淡蓝色草蓝蝴蝶(Pseudozizeeria maha)的翅鳞片中的类黄酮螯合。】 复制标题 收藏 收藏
    DOI:10.1007/s10265-007-0132-x 复制DOI
    作者列表:Mizokami H,Tomita-Yokotani K,Yoshitama K
    BACKGROUND & AIMS: :Three C-glycosylflavones in the leaves of Oxalis corniculata, the host plant of the lycaenid butterfly pale grass blue (Pseudozizeeria maha), were identified as 6-C-glucosylluteolin (isoorientin), 6-C-glucosylapigenin (isovitexin) and isovitexin 7-methyl ether (swertisin). Comparative spectral and HPLC analyses between the leaf extract of the host plants and the wings of P. maha showed selective uptake of the host-plant flavonoid isovitexin to the wings of the butterfly.
    背景与目标: :被鉴定为蝶形青草蓝(Pseudozizeeria maha)寄主的Oxalis corniculata的叶子中的三个C-糖基黄酮被鉴定为6-C-葡萄糖基酪蛋白(isoorientin),6-C-葡萄糖基芹菜素(isovitexin)和异维新毒素7 -甲醚(swertisin)。寄主植物的叶提取物与P. maha的翅膀之间的比较光谱和HPLC分析表明,寄主植物的类黄酮异黄酮毒素对蝴蝶的翅膀有选择性的吸收。
  • 【大戟大黄提取物和分离的类黄酮的抗溃疡活性。】 复制标题 收藏 收藏
    DOI:10.1002/ptr.4872 复制DOI
    作者列表:Awaad AS,Al-Jaber NA,Moses JE,El-Meligy RM,Zain ME
    BACKGROUND & AIMS: :The total alcohol extracts of Euphorbia cuneata Vahl.(Euphorbiaceae) were screened for antiulcerogenic activity using an ethanol-induced ulcer model at doses of 125, 250 and 500 mg/kg. The extracts possessed antiulcerogenic activity in a dose-dependent manner. Four flavonoidal compounds were isolated and identified as naringenin, aromadendrin, apigenin and 4'-O-methoxy-luteolin-7-O-rhamnoglucoside, each demonstrating antiulcerogenic activity with curative ratios ranging from 75.78% to 88.23%. In addition, the alcohol extracts and isolated compounds were shown to scavenge the 1,1-diphenyl,2-picrylhydrazyl radical by different ratio, with the most effective being 4'-O-methoxy-luteolin-7-O-rhamnoglucoside (91.14%). The antioxidant activity of the alcohol extracts and the isolated compounds may explain the antiulcerogenic properties. No side effects were observed on either liver or kidney functions.
    背景与目标: :使用乙醇诱导的溃疡模型,以125、250和500μmg/ kg的剂量筛选大戟大戟(Euphorbiaceae)的总醇提取物的抗溃疡活性。提取物具有剂量依赖性的抗溃疡活性。分离出四种黄酮类化合物,并将其鉴定为柚皮苷,芳香醛固醇,芹菜素和4'-O-甲氧基-木犀草素-7-O-鼠李糖苷,它们均具有抗溃疡活性,治愈率在75.78%至88.23%之间。此外,醇提取物和分离出的化合物显示出以不同比例清除1,1-二苯基,2-吡啶并肼基的作用,最有效的是4'-O-甲氧基-木犀草素-7-O-鼠李糖苷(91.14% )。醇提取物和分离出的化合物的抗氧化活性可以解释其抗溃疡性。肝或肾功能均未观察到副作用。
  • 【从黄中提取的黄酮类化合物对大鼠肝脏NAD(P)H:醌受体氧化还原酶的抑制作用。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Liu XF,Liu ML,Iyanagi T,Legesse K,Lee TD,Chen SA
    BACKGROUND & AIMS: :The glucuronide conjugates of oroxylin A and two other flavones, baicalein, and wogonin, were isolated from the methanol extract of the herb scutellariae radix (Huang Qin) and were found to be inhibitors of rat liver NAD(P)H:quinone acceptor oxidoreductase (EC 1.6.99.2). Baicalin (baicalein 7-O-glucuronide) and oroxylin-A 7-O-glucuronide are approximately 50-fold more potent than wogonin 7-O-glucuronide. The enzyme kinetic analysis revealed that oroxylin-A 7-O-glucuronide is a competitive inhibitor with respect to NADH (the electron donor), with a Ki value of 63 nM. Considering the similarities of their structures and inhibition kinetics to those of dicoumarol, it is thought that oroxylin-A 7-O-glucuronide and the other two flavonoids bind to an identical site and inhibit this quinone reductase in the same fashion as dicoumarol. The results also suggest that the inhibition of NAD(P)H:quinone acceptor oxidoreductase or another vitamin K reductase by oroxylin-A 7-O-glucuronide and the related flavonoids may be one of the steps associated with the anticoagulation action of the herb. These compounds are potentially useful anticoagulant drugs.
    背景与目标: :从中药黄methanol的甲醇提取物中分离得到了木犀草素A和其他两种黄酮,黄ical素和wogonin的葡糖醛酸结合物,它们是大鼠肝脏NAD(P)H的抑制剂:醌受体氧化还原酶(EC 1.6.99.2)。黄ical苷(黄ical素7-O-葡糖醛酸苷)和奥昔林-A 7-O-葡糖醛酸苷的效力比沃戈宁7-O-葡糖醛酸苷的效力高约50倍。酶动力学分析表明,相对于NADH(电子供体),草木素-A 7-O-葡糖醛酸苷是竞争性抑制剂,Ki值为63 nM。考虑到它们的结构和抑制动力学与二氢香豆酚的相似性,据认为,羟氨苄青霉素-A 7-O-葡糖醛酸苷和其他两种类黄酮结合到相同的位点并以与二香豆酚相同的方式抑制该醌还原酶。该结果还表明,通过氧化木素-A 7-O-葡萄糖醛酸苷和相关的类黄酮抑制NAD(P)H:醌受体氧化还原酶或另一种维生素K还原酶可能是与该草药的抗凝作用有关的步骤之一。这些化合物可能是有用的抗凝药物。
  • 【液态发酵过程中某些类黄酮对橙红曲霉李AS3.4384降低霉菌毒素柠檬酸的影响。】 复制标题 收藏 收藏
    DOI:10.1186/s13568-020-0962-7 复制DOI
    作者列表:Wang Y,Gao H,Xie J,Li X,Huang Z
    BACKGROUND & AIMS: :Monascus can produce many beneficial metabolites; however, it can simultaneously also produce citrinin, which seriously limits its application. Therefore, reducing the production of citrinin is of great interest. Herein, Monascus aurantiacus Li AS3.4384 (MAL) was used to optimize the liquid-state fermentation process and investigate the effects of genistein and other flavonoids on citrinin, pigments, and biomass of MAL. Results showed that citrinin decreased by 80%, pigments and biomass increased by approximately 20% in 12 days with addition of 20.0 g/L rice powder as a carbon source and 2.0 g/L genistein during shaking liquid-state fermentation. Further, genistein, daidzein, luteolin, apigenin, quercetin, baicalein, kaempferol myricetin, and genistin exerted different effects on citrinin production by MAL, with genistein causing the highest reduction in citrinin production during liquid-state fermentation, possibly due to the presence of C5-OH, C4'-OH, and C7-OH. Therefore, genistein can be added to the fermentation process of Monascus to reduce citrinin.
    背景与目标: :红曲霉可以产生许多有益的代谢产物;但是,它同时也可以产生柠檬素,这严重限制了它的应用。因此,减少柠檬绿素的产生是非常令人感兴趣的。在此,使用红曲霉AS3.4384(MA​​L)来优化液体发酵过程,并研究金雀异黄素和其他类黄酮对柠檬素,色素和MAL的生物量的影响。结果显示,在摇动液态发酵过程中,添加20.0 g / L大米粉作为碳源和2.0 g / L染料木黄酮,在12天之内柠檬绿素减少80%,色素和生物量增加约20%。此外,金雀异黄素,黄豆苷元,木犀草素,芹菜素,槲皮素,黄ical素,山emp酚杨梅素和染料木素对MAL产生的桔霉素产生不同的影响,在液体发酵过程中,染料木黄酮引起的桔黄素产生减少最多,可能是由于C5的存在-OH,C4'-OH和C7-OH。因此,染料木黄酮可以添加到红曲霉的发酵过程中,以减少橘皮苷。
  • 【膳食类黄酮的摄入和2型糖尿病的风险:前瞻性队列研究的荟萃分析。】 复制标题 收藏 收藏
    DOI:10.1016/j.clnu.2013.03.011 复制DOI
    作者列表:Liu YJ,Zhan J,Liu XL,Wang Y,Ji J,He QQ
    BACKGROUND & AIMS: BACKGROUND & AIMS:Flavonoids may have cardioprotective effects, but epidemiological evidence on the relationship of dietary flavonoids with diabetes has not been systematically assessed. To examine the association between dietary flavonoids and type 2 diabetes, we performed a meta-analysis on this topic. METHODS:We searched PubMed through March 2013 for relevant cohort studies that assessed total flavonoids and type 2 diabetes risks. A fixed-effect model was used to calculate the summary risk estimates. RESULTS:Four articles consisting of 6 prospective cohorts that involved 18,146 cases and 284,806 participants were identified. The summary relative risk (RR) of type 2 diabetes for the highest intake of total flavonoids compared with the lowest was 0.91 (95% confidence interval (CI): 0.87-0.96). Furthermore, an increase in the total flavonoids intake of 500mg/d was associated with a significant risk reduction of 5% (RR=0.95, 95% CI: 0.91-0.98). In subgroup analyses, the observed beneficial effects were observed in US population, in those mean age>40 years old people and in studies ≥20 years in duration. CONCLUSIONS:The present meta-analysis indicates that consumption of dietary total flavonoids is associated with a reduced risk of type 2 diabetes.
    背景与目标: 背景与目的:类黄酮可能具有心脏保护作用,但关于饮食类黄酮与糖尿病关系的流行病学证据尚未得到系统评估。为了检查饮食中类黄酮与2型糖尿病之间的关系,我们对该主题进行了荟萃分析。
    方法:我们在2013年3月之前的PubMed中搜索了相关的队列研究,以评估总类黄酮和2型糖尿病的风险。使用固定效应模型来计算汇总风险估计。
    结果:确定了由6个前瞻性队列组成的4篇文章,涉及18,146例病例和284,806名参与者。总黄酮摄入量最高而最低总摄入量的2型糖尿病汇总相对危险度(RR)为0.91(95%置信区间(CI):0.87-0.96)。此外,总黄酮摄入量增加500mg / d可使风险显着降低5%(RR = 0.95,95%CI:0.91-0.98)。在亚组分析中,在美国人群,平均年龄> 40岁的人群以及持续时间≥20年的研究中观察到了有益的效果。
    结论:本荟萃分析表明,饮食中总黄酮的摄入与2型糖尿病的风险降低有关。
  • 【在体外菌根形成过程中,变异牛肝菌引起了苏格兰松树幼苗中各个多胺和类黄酮含量的显着变化。】 复制标题 收藏 收藏
    DOI:10.1093/jxb/erl209 复制DOI
    作者列表:Niemi K,Julkunen-Tiitto R,Häggman H,Sarjala T
    BACKGROUND & AIMS: :Changes in the concentrations of individual flavonoids and polyamines (PAs) in Scots pine (Pinus sylvestris L.) cotyledonary seedlings were studied during the establishment of an ectomycorrhizal (ECM) symbiosis with two Suillus variegatus strains in vitro. Both flavonoids and PAs were analysed after 3, 7, and 14 d in dual culture, and changes in concentrations were compared with growth of the seedlings. Both S. variegatus strains caused similar responses in Scots pine seedlings. Free putrescine accumulated immediately but only transiently after inoculation. This was followed by continuous accumulation of PA conjugates in needles and stems, and free spermidine and spermine in roots, which was accompanied by mycorrhiza formation and improved growth. The fungi induced lateral root formation and main root and primary needle elongation. Inoculation caused no qualitative changes in flavonoid composition, while quantitative changes in flavonols, catechins, and condensed tannins were observed in shoots during mycorrhiza formation. These results indicate that in this in vitro system conjugated PAs and specific flavonoids, generally related to the plant's defence reactions, did not play a major role in the regulation of the establishment of the ectomycorrhizal (ECM) symbiosis in Scots pine roots. The results also clearly show that positive growth responses in shoots and roots due to S. variegatus were supported by different and highly specific changes in the synthesis of both primary and secondary metabolites in these parts of the seedling.
    背景与目标: :在建立带有两种牛肝菌的外生菌根(ECM)共生过程中,研究了苏格兰松(Pinus sylvestris L.)子叶幼苗中单个类黄酮和多胺(PAs)浓度的变化。在双重培养的第3、7和14天后分析了类黄酮和PA,并将浓度的变化与幼苗的生长进行了比较。两种S. variegatus菌株在苏格兰松树幼苗中引起相似的响应。游离腐胺立即积累,但仅在接种后短暂积累。随后,PA缀合物在针和茎中不断积累,根中游离亚精胺和亚精胺不断积累,并伴有菌根的形成和生长的改善。真菌诱导侧根形成以及主根和主针伸长。接种不会引起菌根形成过程中黄酮类成分的定性变化,而在芽中观察到了黄酮醇,儿茶素和缩合单宁的定量变化。这些结果表明,在这种体外系统中,通常与植物的防御反应有关的共轭PA和特定的类黄酮在调节苏格兰松树根中的根外菌根(ECM)共生的过程中没有发挥主要作用。结果也清楚地表明,由变异链球菌引起的芽和根中的正生长响应受到幼苗这些部分中初级和次级代谢产物合成的不同且高度特异性的变化的支持。
  • 【天然黄酮,黄ical素和菊花素的卤化作用增强了它们对人蛋白激酶CK2的亲和力。】 复制标题 收藏 收藏
    DOI:10.1002/iub.2298 复制DOI
    作者列表:Marzec E,Świtalska M,Winiewska-Szajewska M,Wójcik J,Wietrzyk J,Maciejewska AM,Poznański J,Mieczkowski A
    BACKGROUND & AIMS: :A series of halogenated derivatives of natural flavonoids: baicalein and chrysin were designed and investigated as possible ligands for the catalytic subunit of tumor-associated human kinase CK2. Thermal shift assay method, in silico modeling, and high-performance liquid chromatography-derived hydrophobicity together with IC50 values determined in biochemical assay were used to explain the ligand affinity to the catalytic subunit of human protein kinase CK2. Obtained results revealed that substitution of baicalein and chrysin with halogen atom increases their binding affinity to hCK2α, and for 8-chlorochrysin the observed effect is even stronger than for the reference CK2 inhibitor-4,5,6,7-tetrabromo-1H-benzotriazole. The cytotoxic activities of the baicalein and chrysin derivatives in the in vitro model have been evaluated for MV4-11 (human biphenotypic B myelomonocytic leukemia), A549 (human lung adenocarcinoma), LoVo (human colon cancer), and MCF-7 (human breast cancer) as well as on the nontumorigenic human breast epithelial MCF-10A cell lines. Among the baicalein derivatives, the strongest cytotoxic effect was observed for 8-bromobaicalein, which exhibited the highest activity against breast cancer cell line MCF-7 (IC50 10 ± 3 μM). In the chrysin series, the strongest cytotoxic effect was observed for unsubstituted chrysin, which exhibited the highest activity against leukemic cell line MV4-11 (IC50 10 ± 4 μM).
    背景与目标: :设计并研究了一系列天然类黄酮的卤代衍生物:黄ical素和菊花素,作为肿瘤相关人激酶CK2催化亚基的可能配体。使用热位移测定法,计算机模拟和高效液相色谱衍生的疏水性以及在生化测定中确定的IC50值来解释配体对人蛋白激酶CK2催化亚基的亲和力。获得的结果表明,用卤素原子取代黄ical素和菊花素增加了它们与hCK2α的结合亲和力,并且对于8-氯菊花素,观察到的作用甚至比参考CK2抑制剂-4、5、6、7-四溴-1H-苯并三唑还要强。 。黄ical素和菊花素衍生物在体外模型中的细胞毒活性已针对MV4-11(人类双表型B骨髓单核细胞白血病),A549(人类肺腺癌),LoVo(人类结肠癌)和MCF-7(人类乳腺癌)进行了评估癌)以及非致瘤性人乳腺上皮MCF-10A细胞系上。在黄ical素衍生物中,对8-溴黄8-素观察到最强的细胞毒性作用,它对乳腺癌细胞系MCF-7表现出最高的活性(IC50 10±±3μM)。在chrysin系列中,未取代的chrysin观察到最强的细胞毒性作用,对白血病细胞系MV4-11表现出最高的活性(IC50 10±±4μM)。
  • 【磷酸化类黄酮对猪肝羧酸酯酶的抑制作用。】 复制标题 收藏 收藏
    DOI:10.1016/j.cbi.2013.04.010 复制DOI
    作者列表:Wei Y,Peng AY,Huang J
    BACKGROUND & AIMS: :We have recently synthesized a series of phosphorylated flavonoids and identified some of them as potent inhibitors of pancreatic cholesterol esterase (CEase) with excellent selectivity for CEase over acetylcholinesterase (AChE). In the present paper, we investigated the inhibitory activities of these compounds against porcine liver carboxylesterase (CE) since carboxylesterases (CEs) are another family of serine esterases responsible for the metabolism and detoxification of many ester-containing xenobiotics and clinical esterified drugs, and there exists much structural similarity between CEase and CEs. The results indicated that phosphorylated flavonoids exhibited significantly improved inhibition potency toward CE than their parent compounds, and six of them had IC50 values less than 5.0nM. Among all compounds tested, compounds 3d and 3e are the two most potent inhibitors of CE, giving IC50 values of 1.79nM and 1.58nM, respectively. Interestingly, these compounds inhibited CEase and CE with similar structure activity correlations, and those with high inhibitory activities toward CEase could also inhibit CE efficiently. The presences of a free hydroxyl group at position 5 and a phosphate group at position 7 of the phosphorylated flavonoids are favorable to the inhibition of CE. The inhibition mechanism and kinetic characterization studies of the most potent inhibitors revealed that they are irreversible competitive inhibitors.
    背景与目标: :我们最近合成了一系列磷酸化类黄酮,并确定其中一些是胰胆甾醇酯酶(CEase)的强效抑制剂,与乙酰胆碱酯酶(AChE)相比,对CEase具有优异的选择性。在本文中,我们研究了这些化合物对猪肝羧酸酯酶(CE)的抑制活性,因为羧酸酯酶(CEs)是另一种丝氨酸酯酶家族,负责许多含酯异种生物素和临床酯化药物的代谢和解毒作用,因此CEase和CE之间存在很多结构相似性。结果表明,磷酸化的黄酮类化合物对CE的抑制作用比其母体化合物显着提高,其中6种的IC50值小于5.0nM。在所有测试的化合物中,化合物3d和3e是两种最有效的CE抑制剂,IC50值分别为1.79nM和1.58nM。有趣的是,这些化合物以相似的结构活性相关性抑制CEase和CE,而对CEase具有高抑制活性的那些也可以有效地抑制CE。磷酸化类黄酮的5位游离羟基和7位磷酸根的存在有利于抑制CE。对最有效抑制剂的抑制机理和动力学表征研究表明,它们是不可逆的竞争性抑制剂。
  • 【在植物中广泛分布的一些类黄酮和有机酸的抗菌活性。】 复制标题 收藏 收藏
    DOI:10.3390/jcm9010109 复制DOI
    作者列表:Adamczak A,Ożarowski M,Karpiński TM
    BACKGROUND & AIMS: :Among natural substances widespread in fruits, vegetables, spices, and medicinal plants, flavonoids and organic acids belong to the promising groups of bioactive compounds with strong antioxidant and anti-inflammatory properties. The aim of the present work was to evaluate the antibacterial activity of 13 common flavonoids (flavones, flavonols, flavanones) and 6 organic acids (aliphatic and aromatic acids). The minimal inhibitory concentrations (MICs) of selected plant substances were determined by the micro-dilution method using clinical strains of four species of pathogenic bacteria. All tested compounds showed antimicrobial properties, but their biological activity was moderate or relatively low. Bacterial growth was most strongly inhibited by salicylic acid (MIC = 250-500 μg/mL). These compounds were generally more active against Gram-negative bacteria: Escherichia coli and Pseudomonas aeruginosa than Gram-positive ones: Enterococcus faecalis and Staphylococcus aureus. An analysis of the antibacterial effect of flavone, chrysin, apigenin, and luteolin showed that the presence of hydroxyl groups in the phenyl rings A and B usually did not influence on the level of their activity. A significant increase in the activity of the hydroxy derivatives of flavone was observed only for S. aureus. Similarly, the presence and position of the sugar group in the flavone glycosides generally had no effect on the MIC values.
    背景与目标: :在水果,蔬菜,香料和药用植物中广泛分布的天然物质中,类黄酮和有机酸属于有希望的具有强抗氧化剂和抗炎特性的生物活性化合物。本工作的目的是评估13种常见黄酮类化合物(黄酮,黄酮醇,黄烷酮)和6种有机酸(脂族和芳族酸)的抗菌活性。通过微量稀释法,使用四种病原菌的临床菌株,通过微稀释法确定了选定植物物质的最低抑菌浓度(MICs)。所有测试的化合物均显示出抗菌性能,但其生物学活性中等或相对较低。水杨酸(MIC = 250-500μg/ mL)对细菌的生长有最强的抑制作用。这些化合物通常对革兰氏阴性菌(大肠杆菌和铜绿假单胞菌)的活性要比革兰氏阳性菌(粪肠球菌和金黄色葡萄球菌)高。黄酮,菊花,芹菜素和木犀草素的抗菌作用分析表明,苯环A和B中羟基的存在通常不会影响其活性水平。仅对于金黄色葡萄球菌,黄酮的羟基衍生物的活性显着增加。类似地,黄酮糖苷中糖基的存在和位置通常对MIC值没有影响。
  • 【来自沙特阿拉伯的Euryops arabicus的新甲氧基化类黄酮对人乳腺癌的选择性细胞毒作用。】 复制标题 收藏 收藏
    DOI:10.1016/j.ejmech.2013.05.025 复制DOI
    作者列表:Alarif WM,Abdel-Lateff A,Al-Abd AM,Basaif SA,Badria FA,Shams M,Ayyad SE
    BACKGROUND & AIMS: :The chloroform-methanol extract of Euryops arabicus, collected from Saudi provenance, yielded a new kaurane diterpene (1) and seven methoxylated flavones (2-8), two of which are new (2 and 3). Structures of the compounds were elucidated through interpretation of spectral data of NMR, MS and comparison with literature values. All compounds were evaluated for their anti-tumor activities, employing four different cancer cell lines (WI-38, VERO, HepG2 and MCF-7), ABTS free radical scavenging and immunemodulatory effects. All metabolites had considerable antioxidant and immunestimulatory effects. All compounds showed anticancer activity with IC₅₀ in range 10-125 μM, whilst 2 and 6 showed significant anti-proliferative activity against HepG2 (IC₅₀ = 20 and 15 μM) and MCF-7 (IC₅₀ = 15 and 10 μM), respectively. This effect was attributed to significant S-phase cell cycle arrest.
    背景与目标: :从沙特阿拉伯产地采集的欧亚大陆的氯仿-甲醇提取物产生了一个新的月桂烷二萜(1)和七个甲氧基化的黄酮(2-8),其中两个是新的(2和3)。通过解释NMR,MS的光谱数据并与文献值进行比较来阐明化合物的结构。使用四种不同的癌细胞系(WI-38,VERO,HepG2和MCF-7),ABTS自由基清除和免疫调节作用,评估了所有化合物的抗肿瘤活性。所有代谢产物均具有相当大的抗氧化和免疫刺激作用。所有化合物均显示出抗癌活性,IC 50范围为10-125μM,而2和6分别显示出对HepG2(IC 50 = 20和15μM)和MCF-7(IC 50 = 15和10μM)的显着抗增殖活性。该作用归因于显着的S期细胞周期停滞。
  • 【黄酮类化合物对心肌细胞的氧化剂清除和缺血再灌注损伤的比较作用。】 复制标题 收藏 收藏
    DOI:10.1016/j.ejphar.2007.03.037 复制DOI
    作者列表:Chang WT,Shao ZH,Yin JJ,Mehendale S,Wang CZ,Qin Y,Li J,Chen WJ,Chien CT,Becker LB,Vanden Hoek TL,Yuan CS
    BACKGROUND & AIMS: :Since flavonoids scavenge reactive oxygen species, they may potentially protect against ischemia/reperfusion injury. This study compared the scavenging capacity of specific flavonoids towards different reactive oxygen species. Whether the differential oxidant scavenging capacity correlated with their protective efficacy in ischemia/reperfusion injury of cardiomyocytes was determined. The free radical scavenging capacity of five flavonoids (wogonin, baicalin, baicalein, catechin and procyanidin B2) was analyzed using electron spin resonance spectrometry for 3 radicals: 1,1-diphenyl-2picrylhydrazyl (DPPH), superoxide and hydroxyl radical. A well-established chick cardiomyocyte model of ischemia (1 h)/reperfusion (3 h) was used to evaluate flavonoid-induced protection against ischemia/reperfusion injury in chronic treatment (pretreated 72 h and treated through ischemia/reperfusion) and acute treatment protocols (during ischemia/reperfusion or only at reperfusion). The cell viability was assessed by propidium iodide. The DPPH scavenging was most significant with catechin, followed by procyanidin B2, baicalein, baicalin, and wogonin. The superoxide scavenging was, similarly, most significant with catechin, followed by baicalein, procyanidin B2, and baicalin. For hydroxyl radical, only baicalein showed a significant scavenging capacity (>50% reduction in ESR signal). For the cardiomyocyte studies, all flavonoids but wogonin showed protection against ischemia/reperfusion injury in the chronic treatment protocol. When flavonoids were administered only during ischemia/reperfusion, baicalein, procyanidin B2, and catechin significantly reduced cell death. If flavonoids were administered just at reperfusion, only baicalein and procyanidin B2 had protective effects, and the efficacy was less. Flavonoids possess specific but differential radical scavenging capacity, which, in conjunction with the timing of treatment, affects their protective efficacy in cardiomyocytes exposed to ischemia/reperfusion.
    背景与目标: :由于类黄酮清除了活性氧,它们可能潜在地防止缺血/再灌注损伤。这项研究比较了特定类黄酮对不同活性氧的清除能力。确定了不同的清除氧化剂能力与其在心肌细胞的缺血/再灌注损伤中的保护功效相关联。使用电子自旋共振光谱法分析了3种自由基的1,1,1-二苯基-2吡啶并肼基(DPPH),超氧化物和羟基自由基对5种类黄酮(wogonin,黄ical苷,黄ical素,儿茶素和原花青素B2)的自由基清除能力。建立了成熟的局部缺血小鸡心肌细胞模型(1 h /再灌注)(3 h),以评估类黄酮诱导的针对慢性治疗(预处理72 h,通过局部缺血/再灌注)的缺血/再灌注损伤的保护作用(在缺血/再灌注期间或仅在再灌注期间)。通过碘化丙啶评估细胞活力。儿茶素对DPPH的清除作用最为显着,其次是原花青素B2,黄e素,黄and素和Wogonin。同样,儿茶素对超氧化物的清除作用最为显着,其次是黄ical素,原花青素B2和黄ical素。对于羟基自由基,只有黄ical素具有明显的清除能力(ESR信号降低> 50%)。对于心肌细胞研究,在慢性治疗方案中,除了类黄精以外,所有类黄酮均显示出抗缺血/再灌注损伤的保护作用。当仅在局部缺血/再灌注期间施用类黄酮时,黄ical素,原花青素B2和儿茶素可显着降低细胞死亡。如果仅在再灌注时施用类黄酮,则只有黄ical素和原花青素B2具有保护作用,且疗效较差。黄酮类化合物具有特定但不同的自由基清除能力,与治疗时机结合,会影响其对缺血/再灌注心肌细胞的保护作用。
  • 【白花叶中的类黄酮产品可促进淋巴母细胞凋亡。】 复制标题 收藏 收藏
    DOI:10.1080/01635581.2012.717680 复制DOI
    作者列表:Jihed B,Bhouri W,Ben Sghaier M,Bouhlel I,Kriffi M,Skandrani I,Dijoux FM,Ghedira K,Chekir-Ghedira L
    BACKGROUND & AIMS: :In this report, the ethyl acetate extract and its major constituent, isorhamnetin 3-o-robinobioside (I3-O-Rob), from Nitraria retusa (N. Retusa) leaf extracts were evaluated for their ability to induce apoptosis in human lymphoblastoid cells (TK6). Apoptosis of TK6 cell line was carried out using DNA fragmentation, poly ADP-ribose polymerase (PARP) cleavage with reference to caspase-3 activity. These tested products, from N. Retusa, enhanced the apoptosis effects in the tested cancer cell line. This result was confirmed by DNA fragmentation and PARP cleavage indicating a release of caspase-3 level. Our results indicate that the original ethyl acetate extract and the I3-O-Rob have a great antiproliferative effect on human lymphoblastoid cells (TK6), which may be due to their involvement in the apoptotic pathway.
    背景与目标: :在此报告中,评估了白花叶提取物(N. Retusa)叶提取物中的乙酸乙酯提取物及其主要成分异鼠李素3-o-robinobioside(I3-O-Rob)在人淋巴母细胞中诱导凋亡的能力。 (TK6)。参考caspase-3活性,使用DNA片段化,聚ADP-核糖聚合酶(PARP)切割进行TK6细胞系的凋亡。这些来自N. Retusa的被测产品增强了被测癌细胞系中的细胞凋亡作用。 DNA断裂和PARP裂解表明caspase-3水平的释放证实了这一结果。我们的结果表明,原始的乙酸乙酯提取物和I3-O-Rob对人淋巴母细胞(TK6)具有很大的抗增殖作用,这可能是由于它们参与了凋亡途径。
  • 【饲喂高脂饮食的小鼠天花粉Tri种子油和类黄酮的降血脂和抗氧化活性。】 复制标题 收藏 收藏
    DOI:10.1111/jfbc.13272 复制DOI
    作者列表:Hou Z,Zhu L,Meng R,Wang B
    BACKGROUND & AIMS: :Trichosanlhes kirilowii Maxim seed oil (TSO) is rich in conjugated linolenic acids, and the flavonoids (FLA) combined with n-3 fatty acids can effectively change the plasma antioxidant capacity. Hyperlipidemia and oxidative stress are one of the most important risk factors for cardiovascular disease. This study aims to evaluate the effect of the TSO, FLA, and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice. TSO and TSOFLA administration resulted in a significant decline in serum levels of total cholesterol, triglycerides, and low density lipoprotein-cholesterol. TSOFLA improved the hepatic and serum antioxidant status as assessed by superoxide dismutase, glutathione peroxidase activities, and reduced the levels of lipid peroxidation. Hematoxylin-eosin staining of liver and aorta tissue has shown a marked reduction of the hyperlipidemia-induced lesions by gavage TSOFLA. Compared with TSO and FLA, TSOFLA has more significant hypolipidemic and antioxidant activities, which effects may be correlated to the synergy between TSO and FLA. PRACTICAL APPLICATIONS: Dyslipidemia is a common metabolic disorder, which is characterized by triglyceride levels increased, total cholesterol, and low-density lipoprotein cholesterol. Lipid-lowering treatment can reduce the expansion of coronary atherosclerosis, and particular the dietary lipids have important roles in controlling the concentrations of these risk factors. This is the first study evaluating the hypolipidemic and antioxidant activities effects of Trichosanlhes kirilowii Maxim seed oil (TSO), flavonoids (FLA), and TSO combined with FLA (TSOFLA) intake on hyperlipemia mice caused by a high-fat diet. The pharmacological effects of dietary TSOFLA are correlated to its high content of unsaturated fatty acids and flavonoids. This information can be of interest to the development of food supplements in the field of diseases associated with high-fat intakes such as cardiovascular diseases and adiposis.
    背景与目标: :Trichosanlhes kirilowi​​i Maxim种子油(TSO)富含共轭亚麻酸,而类黄酮(FLA)与n-3脂肪酸结合可有效改变血浆抗氧化能力。高脂血症和氧化应激是心血管疾病最重要的危险因素之一。这项研究旨在评估TSO,FLA和TSO联合FLA(TSOFLA)摄入对高脂血症小鼠的影响。 TSO和TSOFLA给药导致血清总胆固醇,甘油三酸酯和低密度脂蛋白胆固醇水平显着下降。通过超氧化物歧化酶,谷胱甘肽过氧化物酶活性评估,TSOFLA可改善肝和血清抗氧化状态,并降低脂质过氧化水平。食管TSOFLA对肝脏和主动脉组织的苏木精-伊红染色显示出高脂血症诱导的病变的明显减少。与TSO和FLA相比,TSOFLA具有更显着的降血脂和抗氧化活性,其作用可能与TSO和FLA之间的协同作用有关。实际应用:血脂异常是一种常见的代谢紊乱,其特征是甘油三酸酯水平升高,总胆固醇和低密度脂蛋白胆固醇。降脂治疗可以减少冠状动脉粥样硬化的扩展,尤其是饮食中的脂质在控制这些危险因素的浓度方面具有重要作用。这是第一项评估Trichosanlhes kirilowi​​i Maxim籽油(TSO),类黄酮(FLA)和TSO联合FLA(TSOFLA)摄入对高脂饮食引起的高脂血症小鼠降血脂和抗氧化活性影响的研究。膳食TSOFLA的药理作用与其高含量的不饱和脂肪酸和类黄酮有关。在与高脂肪摄入有关的疾病(如心血管疾病和脂肪病)领域,该信息可能对食品补充剂的开发很感兴趣。
  • 【不同的类黄酮可刺激NodD1结合至苜蓿中华根瘤菌中的nod基因启动子。】 复制标题 收藏 收藏
    DOI:10.1128/JB.00376-06 复制DOI
    作者列表:Peck MC,Fisher RF,Long SR
    BACKGROUND & AIMS: :NodD1 is a member of the NodD family of LysR-type transcriptional regulators that mediates the expression of nodulation (nod) genes in the soil bacterium Sinorhizobium meliloti. Each species of rhizobia establishes a symbiosis with a limited set of leguminous plants. This host specificity results in part from a NodD-dependent upregulation of nod genes in response to a cocktail of flavonoids in the host plant's root exudates. To demonstrate that NodD is a key determinant of host specificity, we expressed nodD genes from different species of rhizobia in a strain of S. meliloti lacking endogenous NodD activity. We observed that nod gene expression was initiated in response to distinct sets of flavonoid inducers depending on the source of NodD. To better understand the effects of flavonoids on NodD, we assayed the DNA binding activity of S. meliloti NodD1 treated with the flavonoid inducer luteolin. In the presence of luteolin, NodD1 exhibited increased binding to nod gene promoters compared to binding in the absence of luteolin. Surprisingly, although they do not stimulate nod gene expression in S. meliloti, the flavonoids naringenin, eriodictyol, and daidzein also stimulated an increase in the DNA binding affinity of NodD1 to nod gene promoters. In vivo competition assays demonstrate that noninducing flavonoids act as competitive inhibitors of luteolin, suggesting that both inducing and noninducing flavonoids are able to directly bind to NodD1 and mediate conformational changes at nod gene promoters but that only luteolin is capable of promoting the downstream changes necessary for nod gene induction.
    背景与目标: :NodD1是LysR型转录调节剂NodD家族的成员,该家族介导土壤细菌苜蓿中华根瘤菌中结瘤(nod)基因的表达。根瘤菌的每个物种都与一套有限的豆科植物建立了共生关系。这种宿主特异性部分是由于响应宿主植物根系分泌物中的类黄酮混合物,nodD基因依赖于NodD上调。为了证明NodD是宿主特异性的关键决定因素,我们在缺乏内源NodD活性的苜蓿链球菌菌株中表达了来自不同根瘤菌属的nodD基因。我们观察到,根据NodD的来源,nod基因表达是根据不同的类黄酮诱导物而启动的。为了更好地了解类黄酮对NodD的影响,我们分析了用类黄酮诱导物木犀草素处理的苜蓿链球菌NodD1的DNA结合活性。在没有木犀草素的情况下,与没有木犀草素的结合相比,NodD1与nod基因启动子的结合增加。出人意料的是,尽管它们不刺激苜蓿链球菌中的nod基因表达,但黄酮类柚皮素,雌黄醇和黄豆苷元也刺激了NodD1对nod基因启动子的DNA结合亲和力的增加。体内竞争试验表明,非诱导性类黄酮可作为木犀草素的竞争性抑制剂,这表明诱导性和非诱导性类黄酮均能够直接结合NodD1并介导nod基因启动子的构象变化,但只有木犀草素才能够促进下游必需的下游变化。点头基因诱导。
  • 【黄酮类化合物对SARS-CoV 3CL蛋白酶的抑制作用。】 复制标题 收藏 收藏
    DOI:10.1080/14756366.2019.1690480 复制DOI
    作者列表:Jo S,Kim S,Shin DH,Kim MS
    BACKGROUND & AIMS: :There were severe panics caused by Severe Acute Respiratory Syndrome (SARS) and Middle-East Respiratory Syndrome-Coronavirus. Therefore, researches targeting these viruses have been required. Coronaviruses (CoVs) have been rising targets of some flavonoids. The antiviral activity of some flavonoids against CoVs is presumed directly caused by inhibiting 3C-like protease (3CLpro). Here, we applied a flavonoid library to systematically probe inhibitory compounds against SARS-CoV 3CLpro. Herbacetin, rhoifolin and pectolinarin were found to efficiently block the enzymatic activity of SARS-CoV 3CLpro. The interaction of the three flavonoids was confirmed using a tryptophan-based fluorescence method, too. An induced-fit docking analysis indicated that S1, S2 and S3' sites are involved in binding with flavonoids. The comparison with previous studies showed that Triton X-100 played a critical role in objecting false positive or overestimated inhibitory activity of flavonoids. With the systematic analysis, the three flavonoids are suggested to be templates to design functionally improved inhibitors.
    背景与目标: :严重急性呼吸系统综合症(SARS)和中东呼吸系统综合症-冠状病毒引起严重恐慌。因此,需要针对这些病毒的研究。冠状病毒(CoV)已成为某些类黄酮的上升靶标。推测某些类黄酮对CoV的抗病毒活性直接由抑制3C样蛋白酶(3CLpro)引起。在这里,我们应用了类黄酮库来系统地探测针对SARS-CoV 3CLpro的抑制性化合物。已发现草乙素,rhoifolin和果胶素可有效阻断SARS-CoV 3CLpro的酶活性。也使用基于色氨酸的荧光方法确认了三种类黄酮的相互作用。诱导拟合对接分析表明,S1,S2和S3'位点与类黄酮结合。与先前研究的比较表明,Triton X-100在反对类黄酮的假阳性或高估抑制活性中发挥了关键作用。通过系统的分析,建议将这三种类黄酮作为模板来设计功能改进的抑制剂。

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