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Bereich: Suchergebnisse
Publikation Rat multicellular 3D liver microtissues to explore TGF-β1 induced effects(Elsevier, 13.11.2019) Prestigiacomo, Vincenzo; Weston, Anna; Suter-Dick, LauraChronic liver damage can lead to fibrosis, encompassing hepatocellular injury, activation of Kupffer cells (KC), and activation of hepatic stellate cells (HSC). Inflammation and TGF-β1 are known mediators in the liver fibrosis adverse outcome pathway (AOP). The aim of this project was to develop a suitable rodent cell culture model for the investigation of key events involved in the development of liver fibrosis, specifically the responses to pathophysiological stimuli such as TGF-β1 and LPS-triggered inflammation. We optimized a single step protocol to purify rat primary hepatocytes (Hep), HSC and KC cells to generate 3D co-cultures based on the hanging drop method. This primary multicellular model responded to the profibrotic cytokine TGF-β1 (1 ng/mL) with signs of hepatocellular damage, inflammation and ultimately HSC activation (increase in αSMA expression). LPS elicited an inflammatory response characterized by increased expression of cytokines. 3D-monocultures comprising only Hep displayed different responses, underlying that parenchymal and non-parenchymal cells need to be present in the system to recapitulate fibrosis. The data also suggest that pre-activated HSC may reverse to a quiescent phenotype in 3D, probably due to the more physiological conditions.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Development of a DNA-based Assay to Detect and Quantify Tropane Alkaloids Producing Thornapple Contaminations in Processed Food(Schweizerische Chemische Gesellschaft, 29.05.2019) Weston, Anna; Kübler, Eric01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Modelling Alzheimer’s disease in three-dimensional human neural progenitor cultures(09/2018) Gaiser, Carine; Weston, Anna; Suter-Dick, Laura06 - PräsentationPublikation 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 Yeast‑based assays for screening 11β‑HSD1 inhibitors(Springer, 07.03.2016) Vanella, Rosario; Callari, Roberta; Weston, Anna; Heider, Harald; Schwab, Markus S.; Kübler, EricBACKGROUND: Intracellular metabolism of glucocorticoid hormones plays an important role in the pathogenesis of metabolic syndrome and regulates, among many physiological processes, collagen metabolism in skin. At the peripheral level the concentration of active glucocorticoids is mainly regulated by the 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) enzyme, involved in the conversion of cortisone into the biologically active hormone cortisol. Cortisol interacts with the glucocorticoid receptor and regulates the expression of different classes of genes within the nucleus. Due to its implication in glucocorticoid metabolism, the inhibition of 11β-HSD1 activity has become a dominant strategy for the treatment of metabolic syndrome. Moreover, inhibitors of this target enzyme can be used for development of formulations to counteract skin ageing. Here we present the construction of two yeast cell based assays that can be used for the screening of novel 11β-HSD1 inhibitors. RESULTS: The yeast Saccharomyces cerevisiae is used as a host organism for the expression of human 11β-HSD1 as well as a genetically encoded assay system that allows intracellular screening of molecules with 11β-HSD1 inhibitory activity. As proof of concept the correlation between 11β-HSD1 inhibition and fluorescent output signals was successfully tested with increasing concentrations of carbenoxolone and tanshinone IIA, two known 11β-HSD1 inhibitors. The first assay detects a decrease in fluorescence upon 11β-HSD1 inhibition, whereas the second assay relies on stabilization of yEGFP upon inhibition of 11β-HSD1, resulting in a positive read-out and thus minimizing the rate of false positives sometimes associated with read-outs based on loss of signals. Specific inhibition of the ABC transporter Pdr5p improves the sensitivity of the assay strains to cortisone concentrations by up to 60 times. CONCLUSIONS: Our yeast assay strains provide a cost-efficient and easy to handle alternative to other currently available assays for the screening of 11β-HSD1 inhibitors. These assays are designed for an initial fast screening of large numbers of compounds and enable the selection of cell permeable molecules with target inhibitory activity, before proceeding to more advanced selection processes. Moreover, they can be employed in yeast synthetic biology platforms to reconstitute heterologous biosynthetic pathways of drug-relevant scaffolds for simultaneous synthesis and screening of 11β-HSD1 inhibitors at intracellular level.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation P12-040 High throughput in vitro system for nephrotoxicity testing(2015) Suter-Dick, Laura; Prétôt, René; Weston, Anna; Wegner, Irene; Wilmer, Martijn; Nieskens, Tom T.G.; Vulto, Paul; Joore, Jos; Lanz, Henriette; Masereeuw, Rosalinde06 - Präsentation
