Autophagy is an intracellular degradation system of proteins and organelles. It has several roles in the cell under different conditions. That is why; autophagy is highly regulated in the cell. Sirt1 is member of mammalian sirtuins, which are the homologous of yeast silent information regulator 2 (sir2). It regulates several cellular process under different conditions, such as cancer, aging, metabolic regulation and cellular differentiation. It also functions in autophagy regulation by activating autophagy. Mammalian target of rapamycin (mTOR) is a main regulator protein of autophagy. It forms two complexes, which are called mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). Resveratrol is a polyphenol naturally found in several plants. It brings hope for treatment of several diseases. It is indicated as an activator of Sirt1. On the other hand, EX-527 is a novel inhibitor of Sirt1 which binds to the nicotinamide adenine dinucleotide (NAD+) binding pocket of it. LC3A and LC3B are two novel autophagy markers, which are found cytosolic and autophagosomal membrane bound. In this study, we propose to identify the relation between autophagy with mTOR and Sirt1. HeLa cells were exposed to 15 µM of resveratrol and 300 nM of EX-527, only 15 µM of resveratrol, only 300 nM of EX-527 or nothing. Protein concentrations of three experiment groups with four samples in each experiment were determined and western blotting analyses were done. The most LC3A/B accumulation was found in the cells, which were treated with both resveratrol and EX-527. Addition to this, we found that cells, which were treated with resveratrol, were found to have bigger cell size relative to the other experiment sets, indicating that resveratrol has an inhibitory effect on cell growth. On the other hand, cells treated only with EX-527 were found to have smaller cell size and least LC3 accumulation. These results were reproduced in three separate experiment groups. We concluded that resveratrol has an effect on cell growth either via activation of autophagy or by arresting the cell division cycle.
|Uddannelser||Molekylærbiologi, (Bachelor/kandidatuddannelse) Bachelor el. kandidat|
|Udgivelsesdato||22 jun. 2012|