Effect of an anti-atherogenic mediator, sphingosine 1-phosphate on lipid Metabolism

点击翻译按钮获取中文摘要

We assumed that sphingosine 1-phosphate (S1P) in the lipoprotein could be a modifier of lipid metabolism. In this study, using hepatic cells, (1) we selected the new S1P responsive gene and (2) we also try to find a S1P responsive region on the gene of hepatocyte nuclear factor (HNF) 4a, HNF1a and small hetrodimer partner (SHP). These three genes are thought to play important roles on lipid metabolism and reported to respond to S1P.(1)Select a candidate gene responsive to S1P -Using DNA microarrey technique, we selected some genes of which expressions were decreased by S1P. At this time, we used RNA samples from HpG2 cells for the DNA microarrey analysis, since we can not prepare good primary cultured hepatocytes from mouse at this time. Then, we tried to confirm the expressions of these candidates using a real time PCR technique (TaqMan system), however, we failed to obtain the reproduced results. So we next selected some candidates by searching published papers. We examined the gene expressions or the candidates that we obtained from the searching, using TaqMan system. Using this approach, we found the new S1P responsive gene that is neuron-derived orphan receptor-1 (NOR-1). We also confirmed NOR-1 is the S1P responsive gene in mouse primary cultured hepatocytes.(2)HNF4a, HNF1a and SHP gene analysis-We could not obtain any results that these genes are responded to S1P as reported earlier.