chrysin and wogonin

Screening active components from Chinese traditional medicine is an effective approach to discover new drugs or active structures. Cell membrane chromatography (CMC), developed rapidly because of its high sensitivity and effectiveness, has achieved a wide application in screening active components on pathological cells or tissues. However, it is hard to clarify the selectivity between pathological and normal tissues through simply using pathological cells. In this study, a novel comparative two-dimensional (2D) cell membrane chromatography system was established. Briefly, hepatic carcinoma HepG2 CMC columns and normal hepatic L02 CMC columns were simultaneously loaded to screen potential selective antitumor components from Scutellariae Radix by comparing the retention behaviors on two kinds of cells. Totally 13 components in Scutellariae Radix retained on both HepG2/ CMC and L02/ CMC columns. Among them, three components, oroxylin A, wogonin and chrysin, were screened out to perform stronger affinity on HepG2 columns, and in further cell proliferation assay, IC

Topics: Antineoplastic Agents, Phytogenic; Carcinoma, Hepatocellular; Cell Membrane; Cell Proliferation; Chromatography, High Pressure Liquid; Drug Screening Assays, Antitumor; Drugs, Chinese Herbal; Flavanones; Flavonoids; Hep G2 Cells; Humans; Inhibitory Concentration 50; Liver Neoplasms; Mass Spectrometry; Scutellaria baicalensis

Baicalein, wogonin, and their glycosides are major bioactive compounds found in the medicinal plant Scutellaria baicalensis Georgi. These flavones can induce apoptosis in a variety of cancer cell lines but have no effect on normal cells. Furthermore, they have many additional benefits for human health, such as anti-oxidant, antiviral, and liver-protective properties. Here, we report the isolation and characterization of two CYP450 enzymes, SbCYP82D1.1 and SbCYP82D2, which function as the flavone 6-hydroxylase (F6H) and flavone 8-hydroxylase (F8H), respectively, in S. baicalensis. SbCYP82D1.1 has broad substrate specificity for flavones such as chrysin and apigenin and is responsible for biosynthesis of baicalein and scutellarein in roots and aerial parts of S. baicalensis, respectively. When the expression of SbCYP82D1.1 is knocked down, baicalin and baicalein levels are reduced significantly while chrysin glycosides accumulate in hairy roots. SbCYP82D2 is an F8H with high substrate specificity, accepting only chrysin as its substrate to produce norwogonin, although minor 6-hydroxylation activity can also be detected. Phylogenetic analysis suggested that SbCYP82D2 might have evolved from SbCYP82D1.1 via gene duplication followed by neofunctionalization, whereby the ancestral F6H activity is partially retained in the derived SbCYP82D2.

Topics: Apigenin; Cytochrome P-450 Enzyme System; Flavanones; Flavones; Flavonoids; Humans; Phylogeny; Plant Roots; Saccharomyces cerevisiae; Scutellaria baicalensis

Wogonin and astringin were synthesized from inexpensive chrysin and piceid in short steps. The key feature of these syntheses is site-selective transformation. The target molecules were obtained in 27 and 62% yields from the starting materials, respectively.

Topics: Acetylation; Chemistry Techniques, Synthetic; Flavanones; Flavonoids; Glucosides; Humans; Molecular Structure; Stereoisomerism; Stilbenes

Wogonin and baicalein are bioactive flavones in the popular Chinese herbal remedy Huang-Qin (Scutellaria baicalensis Georgi). These specialized flavones lack a 4'-hydroxyl group on the B ring (4'-deoxyflavones) and induce apoptosis in a wide spectrum of human tumor cells in vitro and inhibit tumor growth in vivo in different mouse tumor models. Root-specific flavones (RSFs) from Scutellaria have a variety of reported additional beneficial effects including antioxidant and antiviral properties. We describe the characterization of a new pathway for the synthesis of these compounds, in which pinocembrin (a 4'-deoxyflavanone) serves as a key intermediate. Although two genes encoding flavone synthase II (FNSII) are expressed in the roots of S. baicalensis, FNSII-1 has broad specificity for flavanones as substrates, whereas FNSII-2 is specific for pinocembrin. FNSII-2 is responsible for the synthesis of 4'-deoxyRSFs, such as chrysin and wogonin, wogonoside, baicalein, and baicalin, which are synthesized from chrysin. A gene encoding a cinnamic acid-specific coenzyme A ligase (SbCLL-7), which is highly expressed in roots, is required for the synthesis of RSFs by FNSII-2, as demonstrated by gene silencing. A specific isoform of chalcone synthase (SbCHS-2) that is highly expressed in roots producing RSFs is also required for the synthesis of chrysin. Our studies reveal a recently evolved pathway for biosynthesis of specific, bioactive 4'-deoxyflavones in the roots of S. baicalensis.

Topics: Acyltransferases; Animals; Antioxidants; Apoptosis; Biosynthetic Pathways; Cell Line, Tumor; Cytochrome P-450 Enzyme System; Flavanones; Flavones; Flavonoids; Gene Expression Regulation, Plant; Humans; Mice; Plant Extracts; Plants, Medicinal; Scutellaria baicalensis

The total flavonoids (TFs) were isolated from the leaves of Carya cathayensis Sarg. (LCC), a well-known Chinese medicinal herb commercially cultivated in Tianmu Mountain district, a cross area of Zhejiang and Anhui provinces in China. Five flavonoids, i.e. cardamonin, pinostrobin chalcone (PC), wogonin, chrysin, and pinocembrin were the main components of the TFs. The TFs and these pure compounds suppressed vascular endothelial growth factor (VEGF)-induced angiogenesis as detected in the mouse aortic ring assay, and cardamonin showed the best effect among them. To further elucidate the mechanisms for suppressing angiogenesis of these flavonoids, assays of VEGF-induced proliferation and migration in human umbilical vein endothelial cells (HUVECs) were performed. The TFs, cardamonin, pinocembrin, and chrysin obviously suppressed both VEGF-induced HUVEC proliferation and migration. However, PC and wogonin not only slightly inhibited VEGF-induced proliferation but also remarkably suppressed those of migration in HUVECs. Our further study showed that cardamonin decreased the phosphorylation of ERK and AKT induced by VEGF with a dose-dependent manner in HUVECs. Our findings indicate that the TFs and these pure flavonoids may become potential preventive and/or therapeutic agents against angiogenesis-related diseases.

Topics: Angiogenesis Inhibitors; Animals; Carya; Cell Movement; Cell Proliferation; Chalcones; Drugs, Chinese Herbal; Extracellular Signal-Regulated MAP Kinases; Flavanones; Flavonoids; Human Umbilical Vein Endothelial Cells; Humans; Male; Mice; Plant Leaves; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Vascular Endothelial Growth Factor A

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent that kills various tumor cells without damaging normal tissues. However, many cancers remain resistant to TRAIL. To overcome TRAIL resistance, combination therapies using sensitizers of the TRAIL pathway would be an efficacious approach. To investigate potential sensitizers of TRAIL-induced apoptosis, we used TRAIL-resistant human T cell leukemia virus type 1 (HTLV-1)-associated adult T cell leukemia/lymphoma (ATL) cells as a model system. So far, HTLV-1-associated ATL is incurable by presently known therapies. Here, we show that wogonin and the structurally related natural flavones apigenin and chrysin break TRAIL resistance in HTLV-1-associated ATL by transcriptional down-regulation of c-FLIP, a key inhibitor of death receptor signaling, and by up-regulation of TRAIL receptor 2 (TRAIL-R2). This effect is mediated through transcriptional inhibition of the p53 antagonist murine double minute 2 (Mdm2), leading to an increase in p53 levels and, consequently, to up-regulation of the p53 target gene TRAIL-R2. We also show that these flavones can sensitize to TNFα- and CD95-mediated cell death. Furthermore, we show that wogonin, apigenin, and chrysin also enhance TRAIL-mediated apoptosis in other human cancer cell lines including breast cancer cell line MDA-MB-231, colon cancer cell line HT-29, hepatocellular carcinoma cell line HepG2, melanoma cell line SK-MEL-37, and pancreatic carcinoma cell line Capan-1 by the same mechanism. Thus, our study suggests the potential use of these flavones as an adjuvant for TRAIL-mediated anticancer therapy.

Topics: Antibodies; Antineoplastic Agents; Apigenin; Apoptosis; Biological Products; CASP8 and FADD-Like Apoptosis Regulating Protein; Cell Line, Tumor; Down-Regulation; Drug Resistance, Neoplasm; fas Receptor; Flavanones; Flavones; Flavonoids; Humans; Leukemia, T-Cell; Lymphoma, T-Cell; Proto-Oncogene Proteins c-mdm2; Receptors, TNF-Related Apoptosis-Inducing Ligand; TNF-Related Apoptosis-Inducing Ligand; Transcription, Genetic; Tumor Necrosis Factor-alpha; Tumor Suppressor Protein p53; Up-Regulation

A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of baicalin, wogonoside, baicalein, wogonin, oroxylin A and chrysin in rat plasma, using naringin as an internal standard. After acidifying with HCl, plasma samples were pretreated by liquid-liquid extraction with acetone. Chromatographic separation was accomplished on a Hypersil Gold-C(18) analytical column (2.1×150 mm, 5 μm) utilizing a gradient elution profile and a mobile phase consisting of (A) 0.1% formic acid in water and (B) acetonitrile. Detection was performed by multiple reaction monitoring (MRM) mode using electrospray ionization in the positive ion mode. All analytes showed good linearity over the investigated concentration range (r>0.9900). The lower limit of quantification was 0.5 ng/ml for baicalin, wogonoside, wogonin and oroxylin A, and 1.0 ng/ml for baicalein and chrysin. Intra-day and inter-day precisions (RSD%) were less than 15% and accuracy (RE%) ranged from -6.7% to 5.8%. The validated method was successfully applied to investigate the pharmacokinetics of the major flavonoids of Radix scutellariae extract after oral administration to rats.

Topics: Administration, Oral; Animals; Area Under Curve; Chromatography, Liquid; Drugs, Chinese Herbal; Flavanones; Flavonoids; Glucosides; Half-Life; Limit of Detection; Male; Metabolic Clearance Rate; Plant Extracts; Rats; Rats, Wistar; Reference Standards; Reproducibility of Results; Scutellaria baicalensis; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry

Indoleamine dioxygenase (IDO) is a heme- containing enzyme that catalyzes the oxidation of tryptophan to N-formylkynurenine, kynurenine and the downstream quinolinic acid. Though IDO is physiologically important in maintaining tissue integrity, aberrant IDO expression represses T cell function and promotes regulatory T cells (Treg) in cancer. It additionally exacerbates Alzheimer, depression, Huntington and Parkinson diseases via quinolinic acid. Inhibition of IDO has thus been recently proposed as a strategy for treating cancer and neuronal disorders. In the present study, we have developed a cell-based assay to evaluate the suppressive effect of anti-inflammatory phytochemicals on the enzyme. When stimulated by INF-γ, profound high expressions of IDO-1 mRNA as well as the protein were detected in human neural stem cells (hNSC) and verified by real-time retro-transcribed PCR and western blot analysis, respectively. The protein activity was measured by kynurenine concentration and the assay was validated by dose-responsive inhibition of IDO-1 antagonists including 1-methyltryptaphan, indomethacin and acetylsalicylic acid. Among the tested compounds, apigenin, baicalein, chrysin, and wogonin exhibit a potent repressive activity with IC(50s) comparable to that of indomethacin. The inhibition was further found to be independent of gene expression and protein translation because of the unaltered levels of mRNA and protein expression. Although curcumin displayed a potent inhibitory activity to the enzyme, it appeared to be cytotoxic to hNSCs. Morphological examination of hNSC revealed that baicalein and wogonin at the inhibitory concentrations induced neurite outgrowth. In conclusion, our data shows that certain phytochemicals with 2-phenyl-1-benzopyran-4-one backbone (flavones) attenuate significantly the IDO-1 protein activity without harming hNSCs. The inhibitory activity might have partially contributed to the anti-cancer and neuro-protective property of the compounds.

Topics: Aromatic-L-Amino-Acid Decarboxylases; Cells, Cultured; Flavanones; Flavonoids; Humans; Indoleamine-Pyrrole 2,3,-Dioxygenase; Indomethacin; Interferon-gamma; Neural Stem Cells; RNA, Messenger

Two new dihydropyranocoumarins, scuteflorins A (1) and B (2), together with the known compounds decursin (3), chrysin (4), oroxylin A (5), wogonin (6), 5,7-dihydroxy-8,2'-dimethoxyflavone, dihydrochrysin, dihydrooroxylin A, lupenol, scutellaric acid, pomolic acid, ursolic acid, beta-sitosterol, daucosterol, and palmitic acid, were isolated from the aerial parts of Scutellaria lateriflora, commonly used as a dietary supplement. The structures of 1 and 2 were established by means of 1D and 2D NMR spectra as well as HRMS data. The absolute configuration of coumarins 1 and 2 was determined by comparison of experimental and theoretical calculated CD spectra. The cytotoxicity and antioxidant effects of the methanol extract of this plant and some of the constituent flavonoids were evaluated in vitro.

Topics: Algorithms; Animals; Chlorocebus aethiops; Drug Screening Assays, Antitumor; Flavanones; Flavonoids; HL-60 Cells; Humans; Nuclear Magnetic Resonance, Biomolecular; Pyranocoumarins; Vero Cells

To study the ethyl acetate soluble constituents from the water extractive of Huanglian Jiedutang decoction, which are composed of Rhizoma Coptidis, Radix Scutellariae, Cortex Phellodendri and Fructus Gardeniae, and provide substances foundation for its pharmacokinetic and pharmacodynamic investigation.. The chemical constituents were isolated by various column chromatographic methods and structurally elucidated by NMR and MS techniques.. Thirty-five compounds were isolated, among which twenty compounds have been identified as beta-sitosterol (1), oroxylin A (2), wogonin (3), ursolic acid (4), skullcapflavone I (5), tenaxin I (6), skullcapflavone II (7), limonin (8), 5, 2'-dihydroxy-6, 7, 8, 3'-tetramethoxyflavone (9), chrysin (12), baicalein (17), tenaxin II (19), 5, 7, 2'-trihydroxy-6, 8-dimethoxyflavone (21), shihulimonin A (22), 6, 2'-dihydroxy-5, 7, 8, 6'-tetramethoxyflavone (26), viscidulin II (28), 5, 7, 4'-trihydroxy-8-methoxyflavone (29), 5, 7, 2', 6'-tetrahydroxyflavone (30), wogonin-7-O-beta-D-glucuronide methyl ester (31) and daucosterol (34).. On the basis of reported results of the chemical constituents of Rhizoma Coptidis, Radix Scutellariae, Cortex Phellodendri and Fructus Gardeniae, it was estimated that all flavonoid compounds rised from the Radix Scutellariae, and compounds 8 and 22 rised from Cortex Phellodendri. Compound 22 was identified in the Cortex Phellodendri for the first time.

Topics: Acetates; Drugs, Chinese Herbal; Flavanones; Flavones; Flavonoids; Limonins; Magnetic Resonance Spectroscopy; Sitosterols; Spectrometry, Mass, Electrospray Ionization; Triterpenes; Ursolic Acid

Hypoxia-inducible factor-1 alpha (HIF-1alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1 that is the key regulator of cellular response to low oxygen tension. Under normoxic conditions, HIF-1alpha is continuously degraded by the ubiquitin-proteasome pathway through pVHL (von Hippel-Lindau tumor suppressor protein). Under hypoxic conditions, HIF-1alpha is stabilized and induces the transcription of HIF-1 target genes. Quercetin, a flavonoid with anti-oxidant, anti-inflammatory, and kinase modulating properties, has been found to induce HIF-1alpha accumulation and VEGF secretion in normoxia. In this study, the molecular mechanisms of quercetin-mediated HIF-1alpha accumulation were investigated. Previous studies have shown that, in addition to being induced by hypoxia, HIF-1alpha can be induced through the phosphatidylinositol 3-kinase (PI3K)/Akt and p53 signaling pathways. But our study revealed, through p53 mutant-type as well as p53 null cell lines, that neither the PI3K/Akt nor the p53 signaling pathway is required for quercetin-induced HIF-1alpha accumulation. And we observed that HIF-1alpha accumulated by quercetin is not ubiquitinated and the interaction of HIF-1alpha with pVHL is reduced, compared with HIF-1alpha accumulated by the proteasome inhibitor MG132. The use of quercetin's analogues showed that only quercetin and galangin induce HIF-1/2alpha accumulation and this effect is completely reversed by additional iron ions. This is because quercetin and galangin are able to chelate cellular iron ions that are cofactors of HIF-1/2alpha proline hydroxylase (PHD). These data suggest that quercetin inhibits the ubiquitination of HIF-1/2alpha in normoxia by hindering PHD through chelating iron ions.

Topics: Basic Helix-Loop-Helix Transcription Factors; Cell Hypoxia; Cell Line, Tumor; Flavanones; Flavonoids; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Iron; Leupeptins; Phosphatidylinositol 3-Kinases; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Proto-Oncogene Proteins c-akt; Quercetin; Signal Transduction; Tumor Suppressor Protein p53; Ubiquitination; Von Hippel-Lindau Tumor Suppressor Protein

Dihydrodiol dehydrogenase (DDH) is a member of the aldo-keto reductases superfamily (AKR1C1-AKR1C4), which plays central roles in the metabolism of steroid hormone, prostaglandin and xenobiotics. We have previously detected overexpression of DDH as an indicator of poor prognosis and chemoresistance in human non-small lung cancer (NSCLC). We also found DDH expression to be closely related to chronic inflammatory conditions. The aim of this study was to investigate the links between inflammation, DDH expression and drug resistance in NSCLC cells. We showed that pro-inflammatory mediators including interleukin-6 (IL-6) could induce AKR1C1/1C2 expression in NSCLC cells and increase cellular resistance to cisplatin and adriamycin. This effect was nullified by Safingol, a protein kinase C inhibitor. Moreover, the expression of AKR1C1/1C2 was inversely correlated to NBS1 and apoptosis-inducing factor (AIF). We also showed that IL-6-induced AKR1C1/1C2 expression and drug resistance were inhibited by wogonin and chrysin, which are major flavonoids in Scutellaria baicalensis, a widely used traditional Chinese and Japanese medicine. In conclusion, this study demonstrated novel links of pro-inflammatory signals, AKR1C1/1C2 expression and drug resistance in NSCLC. The protein kinase C pathway may play an important role in this process. Overexpression of AKR1C1/1C2 may serve as a marker of chemoresistance. Further studies are warranted to evaluate wogonin and chrysin as a potential adjuvant therapy for drug-resistant NSCLC, especially for those with AKR1C1/1C2 overexpression.

Topics: 20-Hydroxysteroid Dehydrogenases; Apoptosis; Carcinoma, Non-Small-Cell Lung; Cell Cycle; Cell Line, Tumor; DNA Repair; Dose-Response Relationship, Drug; Doxorubicin; Drug Resistance, Neoplasm; Flavanones; Flavonoids; Humans; Hydroxysteroid Dehydrogenases; Interleukin-6; Lung Neoplasms

A number of thioflavones has been synthesized and evaluated for their iNOS inhibitory activities. Thiowogonin (6) was obtained from naturally occurring chrysin in 5 steps. Other thioflavones were prepared from the corresponding flavones in a single step by the reaction with Lawesson's reagent. The biological activities of thioflavones were not enhanced by the functional group conversion from carbonyl to thiocarbonyl. Compounds 11 and 13 showed potent NO inhibitory activity at high concentration (40 uM), leading to the possible development of novel neuroprotective agents based on wogonin.

Topics: Animals; Cell Line; Enzyme Inhibitors; Flavanones; Flavones; Flavonoids; Lipopolysaccharides; Mice; Nitric Oxide; Nitric Oxide Synthase; Structure-Activity Relationship

A number of wogonin derivatives have been synthesized as congeners of wogonin and evaluated for their inhibitory activities of PGE2 production. Wogonin derivatives modified at the B ring of wogonin were obtained from 2,4-Dihydroxy-3,6-dimethoxyacetophenone (1) via several steps. Most wogonin derivatives exhibited much reduced inhibitory activities against COX-2 catalyzed PGE2 production compared to that of wogonin. Alkylation of 5,7-phenol groups and substitution at the B ring of wogonin generally caused reduction of inhibitory activity.

Topics: Animals; Anti-Inflammatory Agents; Cell Line; Cyclooxygenase 2 Inhibitors; Dinoprostone; Flavanones; Flavonoids; Lipopolysaccharides; Structure-Activity Relationship