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Giannopoulou, C.

Publications and source records attributed to Giannopoulou, C..

2 recordsLinked to original sources

Reversing Nicotine Toxicity: how Platelet-Rich Plasma Enhances Cell Recovery through Autophagy Modulation

BackgroundChronic exposure to nicotine significantly exacerbates periodontitis, a prevalent inflammatory disease, by inducing cellular processes such as autophagy and inflammation in gingival fibroblasts. Current therapies often fail to fully address these cellular alterations in smokers, highlighting a need for innovative therapeutic and generative approaches. ObjectiveThis study explores the therapeutic potential of Platelet-Rich Plasma (PRP), a blood-derived product, to modulate nicotine-induced biological activities in primary gingival fibroblasts. It aims at understanding the underlying cellular mechanisms and assessing the efficacy of PRP as an adjunct treatment for periodontitis in smokers. MethodsGingival fibroblasts were treated with increasing concentrations of nicotine, which led to senescence and autophagy. Subsequent treatment with autologous PRP was evaluated for its effect on the reversion of these processes, by measuring cell migration and proliferation, metabolic activity, as well as by looking at senescence and autophagic markers. A Caenorhabditis elegans model of autophagy was used to assess nicotine and PRP biological activities in an in vivo environment. ResultsNicotine at high concentrations triggered cellular vacuolization, a decrease in metabolism, viability and proliferation that was partially (with 500 ng/ml nicotine) or completely (with 250 ng/ml nicotine) reversed by a concomitant treatment with 10% PRP. Nicotine alone (250 ng/ml) slightly enhanced migration, while concomitant treatment between nicotine and PRP significantly increased their migration potential. In Caenorhabditis elegans, PRP reduced the nicotine-induced autophagic activity, as evidenced by decreased numbers of autophagosome and a higher number of viable worms during adulthood in comparison to nicotine control conditions. A screening of gingival fibroblast secretome revealed a modulation of autophagy-related cytokines in response to nicotine and/or PRP. ConclusionThe findings demonstrate that PRP could effectively inhibit nicotine-induced autophagy gingival fibroblasts, offering insights into its possible use as a therapeutic tool for managing periodontitis in smokers. The study underscores the potential of PRP in altering disease progression by modulating key cellular processes affected by smoking.

cell biology↗

Long-term fasting remodels gut microbial metabolism and host metabolism

Long-term fasting has become a promising research subject for its potential of treating and preventing metabolic diseases. However, little is known about its impact on the functional capacity of the gut microbiome and the combined effect on the serum metabolome. Here, we demonstrate extensive remodelling of the gut microbial ecosystem in humans (n=92) after an average of 9.8 days of fasting ([~]250 kcal / day). Fasting transiently affected the relative abundance of the majority of bacterial species (306 decreased and 210 increased out of 772). Species changes could largely be explained by their genomic repertoire of carbohydrate-active enzymes (CAZymes), which were investigated here for the first time. Fasting induced extensive abundance changes in CAZyme families, depleting families with dietary fibre substrates and increasing families with host-derived glycan substrates. Likewise, we observed extensive changes in the serum metabolome, with 382 out of 721 metabolites significantly affected (246 increased and 136 decreased). In-depth metagenome-metabolome co-variation analysis suggested Oscillibacter species to be key producers of indole-3-propionic acid, a crucial metabolite for cardiometabolic health. Together, our results provide an unprecedented view on the impact of long-term fasting on gut microbiome composition and function.

microbiology↗