Foucaud L, Niot I, Kanda T, Besnard P
Laboratoire de Physiologie de la Nutrition, UPRES 2422, Ecole Nationale Supérieure de Biologie Appliquée à la Nutrition et à l'Alimentation (ENSBANA), Université de Bourgogne, I, Esplanade Erasme, 21000 Dijon, France.
Biochim Biophys Acta. 1998 Mar 30;1391(2):204-12. doi: 10.1016/s0005-2760(97)00213-0.
The effects of glucocorticoids on the regulation of the liver fatty acid-binding protein (L-FABP) were studied in vivo and in primary culture of hepatocytes in rats. No change in L-FABP cytosolic content and mRNA levels occurred after adrenalectomy. By contrast, a twofold decrease in L-FABP expression was found in dexamethasone (Dex) treated rats. In primary culture of rat hepatocytes, insulin did not modify the L-FABP mRNA levels, whereas Dex produced a significant decrease. This down-regulation was independent of specific glucocorticoid receptors, of alteration in the turnover of L-FABP mRNA and did not require a de novo protein synthesis. However, it was totally prevented when 320 microM oleic acid was added in the culture medium. These findings show that the dex-mediated down-regulation of the L-FABP expression found in vivo is not due to a direct endocrine effect, but is likely secondary to changes in cellular lipid metabolism.
在大鼠体内及原代培养的肝细胞中研究了糖皮质激素对肝脏脂肪酸结合蛋白（L-FABP）调节的影响。肾上腺切除术后，L-FABP的胞质含量和mRNA水平未发生变化。相比之下，在地塞米松（Dex）处理的大鼠中发现L-FABP表达下降了两倍。在大鼠原代肝细胞培养中，胰岛素未改变L-FABP的mRNA水平，而Dex则使其显著下降。这种下调与特异性糖皮质激素受体无关，与L-FABP mRNA的周转变化无关，且不需要从头合成蛋白质。然而，当在培养基中添加320μM油酸时，这种下调完全被阻止。这些发现表明，在体内发现的Dex介导的L-FABP表达下调并非由于直接的内分泌作用，而可能继发于细胞脂质代谢的变化。
