罗格列酮对猪脂肪前体细胞分化过程中聚脂相关基因表达模式的影响

Effects of rosiglitazone on expression patterns of the genes involved in adipogenesis during porcine preadipocytes differentiation

为了解罗格列酮对猪脂肪前体细胞诱导分化过程的影响,利用胶原酶消化法分离猪皮下脂肪前体细胞,采用含50nmol/L胰岛素、100nmol/L地塞米松及0.25mmol/L3-异丁基-1-甲基黄嘌呤的分化培养液Ⅰ(对照组)和在分化培养液Ⅰ中添加100nmol/L罗格列酮的分化培养液Ⅱ(实验组)两种诱导分化方法对脂肪前体细胞进行诱导分化,借助实时定量RT-PCR方法检测了细胞分化过程中聚脂相关基因的表达。结果显示:罗格列酮对PPARγ、C/EBPα、FABP4、FASN和GPAT基因的表达有显著的上调作用,而对PPARα有一定的下调作用。试验组中PPARα、PPARγ、C/EBPα、FABP4、FASN和GPAT等基因分别于48h、48h、48h、108h、60h和24h达到表达高峰,此时的表达量分别是诱导前的1.7、48、3.3、487.5、5.8和3.6倍,GPAT同PPARα和FASN基因表达量间均达到显著相关(P<0.05);而对照组中PPARα、PPARγ、C/EBPα、FABP4、FASN和GPAT等基因分别于84h、96h、48h、96h、36h和36h达到表达高峰,此时的表达量分别是诱导前的2.1、11、1.6、216.5、3.5和2.8倍,GPAT同PPARα和FASN基因表达量间均达到极显著相关(P<0.01)。本实验结果表明:罗格列酮不仅可以极大的促进PPARγ和C/EBPα基因的表达,还能让其协同达到表达高峰;PPARγ和C/EBPα可能是调控猪脂肪前体细胞分化的关键转录因子;在脂肪形成过程中,甘油脂类的生物合成可能发生较早,同时PPARα可能主要参与甘油脂类生物合成的调控。

To investigate the effects of rosiglitazone on porcine preadipocytes during the induced differentiation process, we isolated subcutaneous adipose from two-days-old piglets using collagenase-digestion method and cultured preadipocyte cells in the control and experimental medium, respectively. The control group was under the conditons of 10% fetal calf serum in DMEM/F-12 （1：1）, insulin （50 nmol/L）, dexamethasone （100 nmol/L） and l-methyl- 3-isobutylxanthine （0.25 mmol/L）, while the experimental medium was added with 100 nmol/L rosiglitazone. The expression changes of genes asso- ciated with adipogenesis between the two different conditons were measured by using qRT-PCR. The results revealed that, in the experimental group, the expression levels of PPARa, PPARy, C/EBPa, FABP4, FASN and GPAT were up-regulated to the maximum at 48 h, 48 h, 48 h, 108 h, 60 h and 24 h after induction, respectively, and the change folds of these genes were 1.7, 48, 3.3, 487.5, 5.8 and 3.6, respectively. While, in the control group, the expression levels of these six genes were upregulated to the maximum at different time points （84 h, 96 h, 48 h, 96 h, 36 h and 36 h, respectively） after induction, and the change folds of these genes were also different （2.1, 11, 1.6, 216.5, 3.5 and 2.8, respectively）. In addition, a good correlation among the expression changes of GPAT and PPARa, FASN were all observed at P〈0.05 in the experimental group and at P〈0.01 in control group. These results indicated that the expression of PPARy, C/EBPa, FABP4, FASN and GPAT were strongly up-regulated, and the expression of PPARa was down-regulated under the effects of rosiglitazon. These results suggest that rosiglitazone has a promotive effect on PPARy and C/EBPa. Here, we present three tentatively conclusions. First, PPARy and C/EBPa might be the key transcriptional factors for preadipocytes differentiation. Second, the phospholipids biosynthesis might appear more earlier during the process of adipogenesis. Third, PPARa might play an important role in the regulation of phospholipids biosynthesis.