Project description:Proving functionality in the host environment is a crucial step in antimicrobial development pipelines. Antibiotics targeting fatty acid synthesis (FASII) of the major pathogen Staphylococcus aureus actively inhibit FASII but do not prevent in vivo growth, as bacteria compensate the FASII block by using environmental fatty acids. We used proteomics and phosphoproteomics to elucidate S. aureus responses to anti-FASII in host-relevant conditions. S. aureus responded to anti-FASII treatment in serum by massive reprogramming. A striking inverse correlation was observed in anti-FASII-adapted S. aureus, between amounts of stress response proteins that increase, and virulence factors that decrease. These findings suggest that anti-FASII adapted cells might be better prepared for survival and less equipped to damage the host. Infection by anti-FASII-adapted versus non-treated S. aureus was challenged in the Galleria mellonella model. Time to mortality was longer in insects infected by anti-FASII-treated bacteria compared to those infected by non-treated S. aureus. However, bacterial counts in infected dead insects were comparable for both groups. These results support the hypothesis that higher stress response and lower virulence factor expression, as shown here in FASII-antibiotic-adapted bacteria, may set the stage for persistent infection
Project description:Non-alcoholic fatty liver disease (NAFLD) is a major public health burden and it covers a spectrum of diseases. NAFLD starts with the accumulation of lipid droplets (LDs) within hepatocytes (steatosis). Part of the challenge of studying the mechanistic processes involved in LD accumulation and their implications on the pathogenesis of human NAFLD is due to the available models. Investigating hepatic LDs in humans is challenging and relies on liver biopsies, meaning only cross-sectional data be obtained. On the other hand, LD patterns in in vitro models are poorly defined and rarely reported. Diacylgylcerol acyltransferase (DGAT)2 is one of two enzymes that carry out the final committed step in triacylglycerol (TAG) synthesis. It is unclear whether the enzymes are able to compensate for each other or whether they have distinct roles. It has been hypothesised that DGAT1 primarily utilises exogenous fatty acids and DGAT2 uses de novo-derived fatty acids. Given the important role of this enzyme in TAG synthesis and accumulation, the aims of this study are first to create a cellular model of intrahepatocellular TAG accumulation by manipulating nutritional substrates and to investigate intracellular metabolism in wildtype and DGAT2 knockout cells under these conditions. The experimental workflow for this study is as follows: Huh7 cells (either wild type or knockout) were grown in media containing 11 mM glucose and 2% human serum (HS) for seven days before additional sugars and fatty acids (FAs) were added for a further seven days. All treatments contained 11 mM glucose and 2% HS, either with 200 µM FAs (low fat low sugar; LFLS), 5.5 mM fructose + 200 µM FAs (low fat high sugar; LFHS) or 5.5 mM fructose + 800 µM FAs (high fat high sugar; HFHS). FA metabolism, lipid droplet characteristics and transcriptomic signatures were investigated.
Project description:It was analyzed whole genome microarray data to describe the changes in gene transcription profile in human MCF-7 cancer cells under the influence of fatty acid extracts from CLA-enriched and non-enriched egg yolks.Those results might be found useful in assessing the application of CLA-enriched egg as a nutraceutics in cancer prevention. Six-condition experiment: CLA, KT, cis9,trans11-CLA, trans10,cis12-CLA, KT+cis9,trans11-CLA and KT+trans10,cis12-CLA vs MCF-7 adenocarcinoma cell line. Two control of expreriment. Three biological replicates and three technical replicates.