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12 Ergebnisse
Ergebnisse nach Hochschule und Institut
Publikation Validation of UHPLC–MS/MS methods for the determination of kaempferol and its metabolite 4-hydroxyphenyl acetic acid, and application to in vitro blood-brain barrier and intestinal drug permeability studies(Elsevier, 05.09.2016) Moradi-Afrapoli, Fahimeh; Oufir, Mouhssin; Walter, Fruzsina R.; Deli, Maria A.; Smiesko, Martin; Zabela, Volha; Butterweck, Veronika; Hamburger, Matthias01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Effects of hops derived prenylflavonoids on TNF-α induced barrier dysfunction in intestinal epithelial cells(American Chemical Society, 2017) Luescher, Sandro; Urmann, Corinna; Butterweck, VeronikaThe human intestine allows the absorption of nutrients while also functioning as a barrier preventing pathogens from entering the mucosal tissues. Increased intestinal permeability is associated with autoimmune, inflammatory, and atopic diseases [1]. Tight junctions (TJ) are specialized junctional complexes forming a seal between adjacent epithelial cells. Hops is a source of prenylflavonoids, including 6- and 8-prenylnaringenin (6-PN, 8-PN), xanthohumol (XN) and isoxanthohumol (IX) for which a variety of biological activities have been described. The aims of this study were to a) establish a cell culture model for barrier dysfunction using TNF-α to induce TJ damage in Caco-2 cells; b) to test if hops-derived prenylflavonoids can prevent TNF-α induced TJ damage; and c) to investigate if 6-PN; 8-PN, XN, and IX can restore TNF-α induced barrier dysfunction. After addition of TNF-α, the TEER value of Caco-2 cells demonstrated a significant decrease compared to the control group. From the tested compounds 6-PN and 8-PN prevented epithelial disruption induced by TNF-α, as assessed by measurement of TEER values. XN and IX also showed preventive effects, which occurred 60h after addition of TNF-α. Finally, it was of interest to determine possible treatment effects of XN, IX, 6-PN and 8-PN. Thus, TNF-α was added to Caco-2 cell monolayers for 24h before all test compounds were added. Under these experimental conditions only 8-PN significantly could antagonize TNF-α induced epithelial barrier dysfunction. Our results show for the first time that 8-PN from hops attenuated a cytokine-induced increase in intestinal epithelial TJ permeability.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Metabolite Profile and Antiproliferative Effects in HaCaT Cells of a Salix reticulata Extract(Thieme, 2017) Corradi, Elisabetta; Schmidt, Nadine; Räber, Nathalie; De Mieri, Maria; Hamburger, Matthias; Potterat, Oliver; Butterweck, VeronikaPhenolic constituents of Salix reticulata (Salicaceae) and antiproliferative activity of an extract and individual compounds were investigated in immortalized human non-tumorigenic keratinocytes (HaCaT). A MeOH extract from aerial parts afforded several flavonoids, including luteolin and apigenin glycosides (2–5 and 9) and catechin (1), two procyanidin fractions, and the phenolic glucosides picein (6), triandrin (7), and salicortin (8). In an adenosine triphosphate assay, the MeOH extract reduced cell viability by approximately 60 % at a concentration of 100 µg/mL. Cell proliferation was assessed with a BrdU incorporation ELISA assay. The extract inhibited proliferation of HaCaT cells in a concentration-dependent manner, with approximately 50 % inhibition at 100 µg/mL. In time-lapse assays, the extract showed distinct inhibitory effects on cell migration at concentrations of 12.5, 25, and 50 µg/mL. The activity of selected constituents was also determined. Luteolin-7-O-β-glucuronide (3) significantly inhibited cell proliferation at concentrations of 10 and 50 µM. In contrast, luteolin-7-O-β-glucopyranoside (2) and a procyanidin fraction (P1) had only weak effects, while picein (6) and salicortin (8) did not affect cell proliferation. Luteolin-7-O-β-glucuronide (10 µM) and, to a lesser extent, the procyanidin fraction (10 µg/mL) also inhibited cell migration.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Saffron Flower Extract Promotes Scratch Wound Closure of Keratinocytes and Enhances VEGF Production(Thieme, 2017) Verjee, Sheela; Garo, Eliane; Pelaez, Sarah; Fertig, Orlando; Hamburger, Matthias; Butterweck, VeronikaDuring saffron (Crocus sativus) spice production, large amounts of floral biowaste are generated. It was the aim of this study to develop a value-added product from saffron floral biowaste to be used as a natural cosmetic ingredient. HPLC-PDA-MS analysis of saffron flower extracts revealed the presence of flavonols with the highest amounts in the acetone extract. Kaempferol-3-O-sophoroside was identified as the main flavonoid in the acetone extract (saffron flower acetone extract). Saffron flower acetone extract and kaempferol-3-O-sophoroside were tested in HaCaT cells for potential effects on cell migration, proliferation, and for anti-inflammatory properties. Saffron flower acetone extract concentration dependently (50–200 µg/mL) augmented cell proliferation, as indicated by an increased BrdU-incorporation, while kaempferol-3-O-sophoroside (1–50 µM) had no effect. Furthermore, treatment of HaCaT cells with saffron flower acetone extract, but not with kaempferol-3-O-sophoroside, concentration-dependently increased vascular endothelial growth factor secretion (control 49.72 pg/mL vs. saffron flower acetone extract at 200 µg/mL 218.60 pg/mL). Cell migration was determined using time-lapse microscopy and a modification of the scratch-wound assay in which saffron flower acetone extract significantly improved wound closure compared to the untreated control. Overproduction of the proinflammatory cytokines interleukin-8 and interleukin-6 in HaCaT cells was induced by TNF-α. Kaempferol-3-O-sophoroside (10–50 µM), but not saffron flower acetone extract, inhibited TNF-α-induced IL-8 secretion. The effect was comparable to 10 µM hydrocortisone (positive control). Interestingly, saffron flower acetone extract further increased IL-6 levels in TNF-α-treated HaCaT cells in a concentration-dependent manner. In summary, the pronounced wound healing properties of saffron flower acetone extract present a promising application for the cosmetic industry.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Permeation characteristics of hypericin across Caco-2 monolayers in presence of singe flavonoids, defined flavonoid mixtures or Hypericum extract matrix(Wiley, 2017) Verjee, Sheela; Kelber, Olaf; Kolb, Christiane; Abdel-Aziz, Heba; Butterweck, VeronikaObjectives The major aim of this study was to get a detailed understanding of the exposure and fate of hypericin in the Caco-2 cell system when combined with various flavonoids, mixtures of flavonoids or Hypericum perforatum extract matrix (STW3-VI). Methods The permeation characteristics of hypericin in the absence or presence of quercetin, quercitrin, isoquercitrin, hyperoside and rutin were tested. Hypericin (5 μm) was mixed with single flavonoids (20 μm) or with different flavonoid combinations (each flavonoid 4 or 10 μm, total flavonoid concentration: 20 μm). Further, the uptake of hypericin (5 μm) in the presence of H. perforatum extract matrix (7.25, 29 and 58 μg/ml) was studied. Key findings Following application of hypericin to the apical side of the monolayer, only negligible amounts of the compound were found in the basolateral compartment. From all tested flavonoids, only quercitrin increased the basolateral amount of hypericin. Dual flavonoid combinations were not superior compared to the single combinations. The amount of hypericin in the basolateral compartment increased concentration-dependently in the presence of extract matrix (from 0 to 7.5%). Conclusion Comparing the effects of various flavonoid mixtures vs the extract matrix, it can be concluded that, besides flavonoids, the extract seems to contain further compounds (e.g. phenolic acids or proanthocyanidins) which substantially improve the permeation characteristics of hypericin.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation In vitro modulation of inflammatory target gene expression by a polyphenol-enriched fraction of rose oil distillation waste water(Elsevier, 2016) Weston, Anna; Rausenberger, Julia; Butterweck, Veronika; Wedler, JonasClassical production of rose oil is based on water steam distillation from the flowers of Rosa damascena. During this process, large quantities of waste water accrue which are discharged to the environment, causing severe pollution of both, groundwater and surface water due to a high content of polyphenols. We recently developed a strategy to purify the waste water into a polyphenol-depleted and a polyphenol-enriched fraction RF20-(SP-207). RF20-(SP-207) and sub-fraction F(IV) significantly inhibited cell proliferation and migration of HaCaT cells. Since there is a close interplay between these actions and inflammatory processes, here we focused on the fractions' influence on pro-inflammatory biomarkers. HaCaT keratinocytes were treated with RF20-(SP-207), F(IV) (both at 50 μg/mL) and ellagic acid (10 μM) for 24 h under TNF-α (20 ng/mL) stimulated and non-stimulated conditions. Gene expression of IL-1β, IL-6, IL-8, RANTES and MCP-1 was analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and cellular protein secretion of IL-8, RANTES and MCP-1 was determined by ELISA based assays. RF20-(SP-207) and F(IV) significantly decreased the expression and cellular protein secretion of IL-1β, IL-6, IL-8, RANTES and MCP-1. The diminishing effects on inflammatory target gene expression were slightly less pronounced under TNF-α stimulated conditions. In conclusion, the recovered polyphenol fraction RF20-(SP-207) from rose oil distillation waste water markedly modified inflammatory target gene expression in vitro, and, therefore, could be further developed as alternative treatment of acute and chronic inflammation.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Pharmacokinetics and in vitro blood-brain barrier screening of the plant-derived alkaloid tryptanthrin(Thieme, 2016) Jähne, Evelyn A.; Eigenmann, Daniela E.; Sampath, Chethan; Butterweck, Veronika; Culot, Maxime; Cecchelli, Roméo; Gosselet, Fabien; Walter, Fruzsina R.; Deli, Maria A.; Smiesko, Martin; Hamburger, Matthias; Oufir, MouhssinThe indolo[2,1-b]quinazoline alkaloid tryptanthrin was previously identified as a potent anti-inflammatory compound with a unique pharmacological profile. It is a potent inhibitor of cyclooxygenase-2, 5-lipooxygenase-catalyzed leukotriene synthesis, and nitric oxide production catalyzed by the inducible nitric oxide synthase. To characterize the pharmacokinetic properties of tryptanthrin, we performed a pilot in vivo study in male Sprague-Dawley rats (2 mg/kg bw i. v.). Moreover, the ability of tryptanthrin to cross the blood-brain barrier was evaluated in three in vitro human and animal blood-brain barrier models. Bioanalytical UPLC-MS/MS methods used were validated according to current international guidelines. A half-life of 40.63 ± 6.66 min and a clearance of 1.00 ± 0.36 L/h/kg were found in the in vivo pharmacokinetic study. In vitro data obtained with the two primary animal blood-brain barrier models showed a good correlation with an immortalized human monoculture blood-brain barrier model (hBMEC cell line), and were indicative of a high blood-brain barrier permeation potential of tryptanthrin. These findings were corroborated by the in silico prediction of blood-brain barrier penetration. P-glycoprotein interaction of tryptanthrin was assessed by calculation of the efflux ratio in bidirectional permeability assays. An efflux ratio below 2 indicated that tryptanthrin is not subjected to active efflux.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Hypericum perforatum extract influences permeation characteristics of hypericin across Caco-2 monolayers (P978)(07/2016) Butterweck, Veronika; Verjee, Sheela; Abdel-Aziz, Heba; Kelber, Olaf06 - PräsentationPublikation Effects of hops derived prenylflavonoids on TNF-α induced barrier dysfunction in intestinal epithelial cells(07/2016) Butterweck, Veronika; Luescher, Sandro; Urmann, Corinna06 - PräsentationPublikation Polyphenols as Biogenic Additives and Value Added Products(09/2016) Butterweck, Veronika06 - Präsentation