Real-time quantitative RT-PCR determination of SREBP-1 and SREBP-2 mRNA levels in SM-enriched adipocytes or unmodulated adipocytes.

a The control group was expressed as 1. P<0.0001, P<0.001, P<0.01 and P<0.05; SM-, GSH-, and PPMP-treated cells compared with untreated cells.
3T3-F442A adipocytes were treated with 15 μM natural SM (SM-LA, 24 h), 10 mM GSH (24 h), 20 μM PPMP (24 h) or vehicle. The mRNA levels of the studied genes were determined. The results are expressed as-fold variations over respective controls (R) after normalization to β-actin, as indicated in the Materials and methods. R values superior or equal to 2 were considered positive regulation of gene expression, whereas values lower than 0.5 indicated negative regulation. The results presented are the means of 3 independent experiments, which were performed twice each in duplicate.

[a] 对照组的相对表达量以1计，显著性差异判定阈值分别为P<0.0001、P<0.001、P<0.01及P<0.05，比较组别为经鞘磷脂（SM）、谷胱甘肽（GSH）及PPMP处理的细胞与未处理细胞。
3T3-F442A脂肪细胞分别经15 μM天然鞘磷脂（SM-LA，处理24 h）、10 mM谷胱甘肽（GSH，处理24 h）、20 μM PPMP（处理24 h）或溶剂对照处理。
本研究测定了目标基因的mRNA表达水平，结果以相对于各自对照组（R）的倍数变化表示，如材料与方法部分所述，以β-肌动蛋白作为内参基因完成归一化校正。
当R值大于或等于2时，判定为基因表达正调控；当R值低于0.5时，则判定为基因表达负调控。
本次展示的结果为3次独立实验的平均值，每项实验均重复2次，每次重复设置双复孔。