Role of mammalian sirtuin 1 (SIRT1) in lipids metabolism and cell proliferation of goose primary hepatocytes.

Our result showed in the fatty liver formation induced-by overfeeding goose, it was accompanied by an activation of mammalian target of rapamycin (mTOR) pathway and cell proliferation. Recent studies have suggested a crucial role for mammalian sirtuin 1 (SIRT1) in regulating lipid metabolism and cell proliferation, so we hypothesize that resveratrol -activated and nicotinamide -inhibited SIRT1 acts goose hepatocellular lipid metabolism and cell proliferation by mTOR signal pathway. Here we show that both resveratrol and nicotinamide could evidently affect the DNA synthesis rate, the lipids accumulation, the mRNA level and protein content of genes involved in the lipids metabolism, mTOR signal pathway, and the cell cycle progression of goose primary hepatocytes. Moreover, rapamycin decreased the effect of nicotinamide on lipids accumulation and cell proliferation. These findings suggest that SIRT1 functions as a regulator for mTOR signaling and plays an essential role in the regulation of hepatocyte lipid metabolism and cell proliferation.