chrysin and kaempferol

Several chemical compounds can restore pigmentation in vitiligo through mechanisms that vary according to disease etiology. In the present study, we investigated the melanogenic activity of six structurally distinct compounds, namely, scopoletin, kaempferol, chrysin, vitamin D

Topics: Alkaloids; Animals; Benzodioxoles; Benzyl Compounds; Cholecalciferol; Flavonoids; Humans; Kaempferols; Melanins; Monophenol Monooxygenase; Pigmentation; Piperidines; Polyunsaturated Alkamides; Purines; Scopoletin; Vitiligo; Zebrafish

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Aspartate Aminotransferases; Biomarkers; Colony Count, Microbial; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Flavonoids; Gene Expression; Kaempferols; Leukocyte Count; Liver; Male; Mice; Mice, Inbred ICR; Nitric Oxide; Peroxidase; Sepsis; Survival Analysis; Tumor Necrosis Factor-alpha

Death-associated protein kinase 1 (DAPK1) is a 160 kDa serine/threonine protein kinase that belongs to the Ca(2+)/calmodulin-dependent protein kinase subfamily. DAPK1 is a possible target for the treatment of acute ischemic stroke and endometrial adenocarcinomas. In the present study, we investigated the binding characteristics of 17 natural flavonoids to DAPK1 using a 1-anilinonaphthalene-8-sulfonic acid competitive binding assay and revealed that morin was the strongest binder among the selected compounds. The crystallographic analysis of DAPK1 and 7 selected flavonoid complexes revealed the structure-binding affinity relationship in atomic-level detail. It was suggested that the high affinity of morin could be accounted for by the ionic interaction between 2'-OH and K42 and that such an interaction would not take place with either cyclin-dependent protein kinases or PIM kinases because of their broader entrance regions. Thus, morin would be a more selective inhibitor of DAPK1 than either of these other types of kinases. In addition, we found that the binding of kaempferol to DAPK1 was associated with a chloride ion. The present study provides a better understanding of the molecular properties of the ATP site of DAPK1 and may be useful for the design of specific DAPK1 inhibitors.

Topics: Adenosine Triphosphate; Allosteric Site; Anilino Naphthalenesulfonates; Binding, Competitive; Crystallography, X-Ray; Death-Associated Protein Kinases; Flavonoids; Kaempferols; Protein Binding; Protein Conformation; Structure-Activity Relationship

Two new diarylheptanoids, 1-(3',5'-dihydroxy-4'-methoxyphenyl)-7-phenyl-3-heptanone (1) and 1-(2',4'-dihydroxy-3'-methoxyphenyl)-7-(4″-methoxyphenyl)-3-heptanone (2), along with known diarylheptanoid yakuchinone A (3), and five flavanoids, tectochrysin (4), chrysin (5), izalpinin (6), kaempferol 7, 4'-dimethyl ether (7), and kaempferide (8) were isolated from the fruits of Alpinia oxyphylla Miq. Their structures were determined by means of spectroscopic methods. Antioxidant activities of all the isolated compounds were evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Compounds 1-3 and 6-8 exhibited potent antioxidant activities in the DPPH assay.

Topics: Alpinia; Antioxidants; Biphenyl Compounds; Diarylheptanoids; Drugs, Chinese Herbal; Flavonoids; Fruit; Guaiacol; Kaempferols; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates

The influence of glucose on the interaction between flavonoids and plasma proteins from healthy humans (HPPs) was investigated. Glucose affected the flavonoid-protein interactions depending upon their structures. Glucose significantly reduced the affinities of HPPs for 6-hydroxyflavone by 10.72 times, slightly weakened the affinities of HPPs for quercetin, 7-hydroxyflavone, and kaempferol, and hardly affected the affinities of HPPs for myricetin, chrysin, and 3,7-dihydroxyflavone on the first day. However, glucose obviously enhanced the affinities of HPPs for 3-hydroxyflavone, luteolin, and apigenin. Glucose significantly weakened the binding affinities of HPPs for chrysin, kaempferol, quercetin, and myricetin by 6.17, 7.94, 14.12, and 112.2 times, when kept at 37 °C under air conditions for 14 days, and the binding affinities of HPPs for 7-hydroxyflavone, luteolin, 3,7-dihydroxyflavone, 3-hydroxyflavone, and 6-hydroxyflavone were slightly decreased by 1.35-, 1.58-, 1.58-, 1.9-, and 2.4-fold. The binding affinity between apigenin and HPP was hardly influenced. Glucose weakened the binding affinities of HPPs for hydroxyflavonoids. The differences between log K(a)(absence) and log K(a)(presence) were bigger for the more lipophilic hydroxyflavonoids, and more lipophilic hydroxyflavonoids are easily affected by glucose, when kept at 37 °C under air conditions for 14 days. These flavonoids with lower hydrogen donor/acceptor numbers prefer to stably interact with HPPs in the presence of glucose. However, other flavonoids with high hydrogen donor/acceptor numbers (multi-hydroxyl flavonoids) were apt to reduce their affinities with HPPs in the presence of glucose.

Topics: Adult; Apigenin; Binding Sites; Binding, Competitive; Blood Glucose; Blood Proteins; Diet; Dietary Supplements; Flavonoids; Glucose; Humans; Hydrogen Bonding; Kaempferols; Luteolin

Thermal burn injury induces inflammatory cell infiltrates in the dermis and thickening of the epidermis. Following a burn injury, various mediators, including reactive oxygen species (ROS), are produced in macrophages and neutrophils, exposing all tissues to oxidative injury. The anti-oxidant activities of flavonoids have been widely exploited to scavenge ROS. In this study, we observed that several flavonoids-kaempferol, quercetin, fisetin, and chrysin-inhibit LPS-induced IL-8 promoter activation in RAW 264.7 cells. In contrast with quercetin and fisetin, pretreatment of kaempferol and chrysin did not decrease cell viability. Inflammatory cell infiltrates in the dermis and thickening of the epidermis induced by burn injuries in mice was relieved by kaempferol treatment. However, the injury was worsened by fisetin, quercetin, and chrysin. Expression of TNF-a induced by burn injuries was decreased by kaempferol. These findings suggest the potential use of kaempferol as a therapeutic in thermal burn-induced skin injuries. [BMB reports 2010; 43(1): 46-51].

Topics: Animals; Burns; Cell Differentiation; Cell Line, Tumor; Flavonoids; Flavonols; Interleukin-8; Kaempferols; Lipopolysaccharides; Mice; Quercetin; Reactive Oxygen Species; Skin; Tumor Necrosis Factor-alpha

Propolis is considered to down-regulate type I allergy, but the effective components of propolis remain unknown. In addition, propolis components vary depending on the area from which they are collected due to variations among wild plants in an area. Therefore, we compared the effects of water and ethanol extracts of propolis from Brazil and China on mast cell degranulation and cytokine production, thereby identifying effective components in propolis. The amount of released beta-hexosaminidase via high-affinity IgE receptor I (Fc epsilon RI) from rat basophilic leukemia (RBL-2H3) cells was used as an index of degranulation. All propolis extracts inhibited degranulation from antigen-stimulated RBL-2H3 cells, but the effective doses differed according to collection areas. The ethanol extract of Chinese propolis, which was the strongest inhibitor of mast cell degranulation, was divided into compounds using normal- and reversed-phase liquid chromatography. The isolated anti-allergic components were identified as chrysin, kaempferol and its derivative, and chrysin was revealed to inhibit IL-4 and MCP-1 production from antigen-stimulated RBL-2H3 cells. HPLC quantification also revealed the Brazilian propolis extract to contain only small amounts of these flavonoids, which suggested that variation in propolis components could affect anti-allergic properties.

Topics: Animals; Anti-Allergic Agents; Basophils; beta-N-Acetylhexosaminidases; Cell Degranulation; Chemokine CCL2; Cytokines; Flavonoids; Interleukin-4; Kaempferols; Mast Cells; Plant Extracts; Propolis; Rats; Receptors, IgE

No clear data are available on how flavonoids from different chemical groups affect root colonization by arbuscular mycorrhizal fungi (AMF) and whether flavonoids affecting the presymbiotic growth of AMF also affect root colonization by AMF. In the present work, we compared the effect of flavones (chrysin and luteolin) and flavonols (kaempferol, morin, isorhamnetin, and rutin) on root colonization (number of entry points and degree of root colonization) of tomato plants (Lycopersicum esculentum L.) with the effect of these flavonoids on the presymbiotic growth of these AMF, which has been reported in a recent study. With all tested AMF (Gigaspora rosea, Gigaspora margarita, Glomus mosseae, and Glomus intraradices) a correlation between the number of entry points and the percentage of root colonization was found. When the number of entry points was high, root colonization was also enhanced. Application of the flavones chrysin and luteolin and of the flavonol morin increased the number of entry points and the degree of colonization,whereas the flavonols kaempferol, isorhamnetin, and rutin showed no effect. These results show that in contrast to their effect on the presymbiotic growth of the AMF on the level of root colonization, the tested flavonoids do not exhibit a genus- and species-specificity. Moreover, comparison of our data with the data obtained by J.M. Scervino, M.A. Ponce, R. Erra-Bassells, H. Vierheilig, J.A. Ocampo, and A. Godeas. (2005a. J. Plant Interact. 15: 22-30) indicates that a positive effect on the hyphal growth of AMF does not necessarily result in an enhanced AM root colonization, further indicating that the mode of action of flavonoids at the level of root colonization is more complex.

Topics: Flavones; Flavonoids; Flavonols; Kaempferols; Luteolin; Mycorrhizae; Plant Roots; Rutin; Solanum lycopersicum; Symbiosis

Up to now, the metabolism of hispidulin (5,7,4'-trihydroxy-6-methoxyflavone), a potent ligand of the central human benzodiazepine receptor, has not been investigated. To elucidate the metabolism of hispidulin in the large intestine, its biotransformation by the pig caecal microflora was studied. In addition, the efficiency of the pig caecal microflora to degrade galangin (3,5,7-trihydroxyflavone), kaempferol (3,5,7,4'-tetrahydroxyflavone), apigenin (5,7,4'-trihydroxyflavone), and luteolin (5,7,3',4'-tetrahydroxyflavone) was investigated. Identification of the formed metabolites was performed by high-performance liquid chromatography (HPLC)-diode array detection, HPLC-electrospray ionization-tandem mass spectrometry, and high-resolution gas chromatography-mass spectrometry. The caecal microflora transformed hispidulin to scutellarein (5,6,7,4'-tetrahydroxyflavone), an effective alpha-glucosidase inhibitor, and 3-(4-hydroxyphenyl)-propionic acid; galangin to phenylacetic acid and phloroglucinol; kaempferol to 4-hydroxyphenylacetic acid, phloroglucinol, and 4-methylphenol; apigenin to 3-(4-hydroxyphenyl)-propionic acid and 3-phenylpropionic acid, and luteolin to 3-(3-hydroxyphenyl)-propionic acid, respectively. To elucidate to what extent different hydroxylation patterns on the B-ring influence the degradation degree of flavonoids, the conversions of galangin and kaempferol as well as that of apigenin and luteolin were compared with those of quercetin (3,5,7,3',4'-pentahydroxyflavone) and chrysin (5,7-dihydroxyflavone), respectively. Regardless of the flavonoid subclass, the presence of a hydroxy group at the 4'-position seems to be a prerequisite for fast breakdown. An additional hydroxy group at the B-ring did not affect the degradation degree.

Topics: Animals; Apigenin; Bacteria; Cecum; Chromatography, High Pressure Liquid; Flavones; Flavonoids; Gas Chromatography-Mass Spectrometry; Humans; Kaempferols; Kinetics; Luteolin; Models, Animal; Quercetin; Spectrometry, Mass, Electrospray Ionization; Swine

Intercellular adhesion molecule-1 (ICAM-1) has been implicated in the processes of inflammation and carcinogenesis. Flavonoids, which are polyphenolic compounds with a wide distribution throughout the plant kingdom, have potent anti-inflammatory properties. We investigated the effects of flavonols (kaempferol, quercetin, and myricetin) and flavones (flavone, chrysin, apigenin, luteolin, baicalein, and baicalin) on the tumor necrosis factor-alpha (TNF-alpha)-stimulated ICAM-1 expression. Among those flavonoids tested, kaempferol, chrysin, apigenin, and luteolin are active inhibitors of ICAM-1 expression. Additional experiments suggested that apigenin and luteolin were actively inhibiting the IkappaB kinase (IKK) activity, the IkappaBalpha degradation, the nuclear factor-kappaB (NF-kappaB) DNA-protein binding, and the NF-kappaB luciferase activity. TNF-alpha-induced ICAM-1 promoter activity was attenuated using an activator protein-1 (AP-1) site deletion mutant, indicating the involvement of AP-1 in ICAM-1 expression. AP-1-specific DNA-protein binding activity was increased by TNF-alpha, and the supershift assay identified the components of c-fos and c-jun. Extracellular signal-regulated kinase (ERK) and p38 were involved in the c-fos mRNA expression, and c-Jun NH(2)-terminal kinase (JNK) was involved in the c-jun mRNA expression. All three mitogen-activated protein kinase (MAPK) activities were inhibited by apigenin and luteolin. In comparison, kaempferol and chrysin only inhibited the JNK activity. The inhibitory effects of apigenin and luteolin on ICAM-1 expression are mediated by the sequential attenuation of the three MAPKs activities, the c-fos and c-jun mRNA expressions, and the AP-1 transcriptional activity. IKK/NF-kappaB pathway is also involved; however, kaempferol- and chrysin-mediated inhibitions are primarily executed through the attenuation of JNK activity, c-jun mRNA expression, and AP-1 activity. The structure-activity relationships are also explored, and the important role of -OH group at positions 5 and 7 of A ring and at position 4 of B ring is noted. Finally, our results suggested that AP-1 seems to play a more significant role than NF-kappaB in the flavonoid-induced ICAM-1 inhibition.

Topics: Apigenin; Drug Interactions; Epithelial Cells; Flavonoids; Flavonols; Gene Expression Regulation; Humans; I-kappa B Kinase; Intercellular Adhesion Molecule-1; JNK Mitogen-Activated Protein Kinases; Kaempferols; Luteolin; Mitogen-Activated Protein Kinases; NF-kappa B; Protein Kinases; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-fos; RNA, Messenger; Transcription Factor AP-1; Tumor Cells, Cultured; Tumor Necrosis Factor-alpha; U937 Cells; Up-Regulation

There is very limited information on cytochrome P450 (P450)-mediated oxidative metabolism of dietary flavonoids in humans. In this study, we used human liver microsomes and recombinant P450 isoforms to examine the metabolism of two flavonols, galangin and kaempferide, and one flavone, chrysin. Both galangin and kaempferide, but not chrysin, were oxidized by human liver microsomes to kaempferol, with K(m) values of 9.5 and 17.8 microM, respectively. These oxidations were catalyzed mainly by CYP1A2 but also by CYP2C9. Consistent with these observations, the human liver microsomal metabolism of galangin and kaempferide were inhibited by the P450 inhibitors furafylline and sulfaphenazole. In addition, CYP1A1, although less efficient, was also able to oxidize the two flavonols. Thus, dietary flavonols are likely to undergo oxidative metabolism mainly in the liver but also extrahepatically.

Topics: Aryl Hydrocarbon Hydroxylases; Cytochrome P-450 CYP1A1; Cytochrome P-450 CYP1A2; Cytochrome P-450 CYP2C9; Cytochrome P-450 Enzyme System; Flavonoids; Humans; Isoenzymes; Kaempferols; Microsomes, Liver; Mutagens; Oxidation-Reduction; Quercetin; Steroid 16-alpha-Hydroxylase; Steroid Hydroxylases; Trisaccharides

Peroxisome proliferator-activated receptor (PPAR)gamma transcription factor has been implicated in anti-inflammatory response. Of the compounds tested, apigenin, chrysin, and kaempferol significantly stimulated PPAR gamma transcriptional activity in a transient reporter assay. In addition, these three flavonoids strongly enhanced the inhibition of inducible cyclooxygenase and inducible nitric oxide synthase promoter activities in lipopolysaccharide-activated macrophages which contain the PPAR gamma expression plasmids. However, these three flavonoids exhibited weak PPAR gamma agonist activities in an in vitro competitive binding assay. Limited protease digestion of PPAR gamma suggested these three flavonoids produced a conformational change in PPAR gamma and the conformation differs in the receptor bound to BRL49653 versus these three flavonoids. These results suggested that these three flavonoids might act as allosteric effectors and were able to bind to PPAR gamma and activate it, but its binding site might be different from the natural ligand BRL49653.

Topics: Animals; Apigenin; Binding, Competitive; Cell Line; Dose-Response Relationship, Drug; Electrophoresis, Polyacrylamide Gel; Flavonoids; Genes, Reporter; Kaempferols; Macrophages; Mice; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Promoter Regions, Genetic; Prostaglandin-Endoperoxide Synthases; Protein Binding; Quercetin; Receptors, Cytoplasmic and Nuclear; Rosiglitazone; Thiazoles; Thiazolidinediones; Transcription Factors

1. Resveratrol, a polyphenolic compound present in grape and wine, has beneficial effects against cancer and protective effects on the cardiovascular system. Resveratrol is sulphated, and the hepatic and duodenal sulphation might limit the bioavailability of this compound. The aim of this study was to see whether natural flavonoids present in wine, fruits and vegetables inhibit the sulphation of resveratrol in the human liver and duodenum. 2. In the liver, IC50 for the inhibition of resveratrol sulphation was 12+/-2 pM (quercetin), 1.0+/-0.04 microM (fisetin), 1.4+/-0.1 microM (myricetin), 2.2+/-0.1 microM (kaempferol) and 2.8+/-0.2 microM (apigenin). Similarly, in the duodenum, IC50 was 15+/-2 pM (quercetin), 1.3+/-0.1 microM (apigenin), 1.3+/-0.5 microM (fisetin), 2.3+/-0.1 microM (kaempferol) and 2.5+/-0.3 microM (myricetin). 3. The type of inhibition of quercetin on resveratrol sulphation was studied in three liver samples and was determined to be non-competitive and mixed in nature. Km (mean+/-SD; microM) was 0.23+/-0.07 (control), 0.40+/-0.08 (5 pM quercetin) and 0.56+/-0.09 (10 pM quercetin). Vmax (mean+/-SD; pmol min(-1) x mg(-1)) was 99+/-11 (control), 73+/-15 (5 pM quercetin) and 57 +/- 10 (10 pM quercetin). Kj and Kies estimates (mean+/-SD) were 3.7+/-1.8 pM and 12.1+/-1.7 pM respectively (p = 0.010). 4. Chrysin was a substrate for the sulphotransferase(s) and an assay was developed for measuring the chrysin sulphation rate in human liver. The enzyme followed Michaelis-Menten kinetics and Km and Vmax (mean+/-SD) measured in four livers were 0.29+/-0.07 microM and 43.1+/-1.9 pmol x min(-1) x mg(-1) respectively. 5. Catechin was neither an inhibitor of resveratrol sulphation nor a substrate of sulphotransferase. 6. These results are consistent with the view that many, but not all, flavonoids inhibit the hepatic and duodenal sulphation of resveratrol, and such inhibition might improve the bioavailability of this compound.

Topics: Aged; Apigenin; Biological Availability; Duodenum; Female; Flavonoids; Flavonols; Fruit; Humans; Kaempferols; Kinetics; Liver; Male; Middle Aged; Quercetin; Resveratrol; Stilbenes; Substrate Specificity; Sulfates; Sulfotransferases; Vegetables; Wine

The effect of five propolis flavonoids on the infectivity and replication of some herpesvirus, adenovirus, coronavirus and rotavirus strains has been studied. Experiments were performed in vitro in cell cultures using the viral plaque reduction technique. The cytotoxicity of flavonoids, including chrysine, kaempferol, acacetin, galangin and quercetin, was evaluated on uninfected monolayers to determine their effect on cell growth and viability. Chrysine and kaempferol caused a concentration-dependent reduction of intracellular replication of herpes-virus strains when monolayers were infected and subsequently cultured in a drug-containing medium. However, virus infectivity was not significantly affected. Acacetin and galangin had no effect on either the infectivity or replication of any of the viruses studied. Quercetin reduced infectivity and intracellular replication, but only at the highest concentrations tested.

Topics: Animals; Cell Line; Flavones; Flavonoids; Humans; Immunoenzyme Techniques; Kaempferols; Molecular Structure; Quercetin; Vero Cells; Viral Plaque Assay; Virus Replication; Viruses

The effects of various flayonoids on RNA synthesis in permeable human fibroblasts or on transcription with mouse RNA polymerase II were studied. Quercetin or kaempferol inhibited transcription in permeable cells but flavone did so only slightly. In the transcription of naked DNA with purified RNA polymerase II, mutagenic quercetin, kaempferol or fisetin strongly inhibited the reaction but non-mutagenic or weakly mutagenic flavone and chrysin inhibited it only weakly. Quercetin seems to inhibit the transcription by interaction with the enzyme.

Topics: Animals; Cell Line; Cell Membrane Permeability; DNA Replication; Flavones; Flavonoids; Flavonols; Humans; Kaempferols; Kinetics; Mice; Quercetin; RNA Polymerase II; Structure-Activity Relationship; Transcription, Genetic