TRANSCRIPTIONAL INDUCTION OF THE FATTY-ACID-BINDING PROTEIN GENE IN MOUSE-LIVER BY BEZAFIBRATE

The mechanism by which hypolipidemic peroxisome proliferators of the f ibrate family induce the liver fatty acid binding protein in liver of rodents is unknown. In order to delineate the level at which this prot ein is induced, the transcriptional activity of the specific gene enco ding for liver fatty acid binding protein was measured in isolated hep atocyte nuclei obtained from male Swiss mice daily force-fed during 7 days with 400 mg/kg body weight bezafibrate. This treatment induced a 4-fold increase in the liver fatty acid binding protein transcription rate. Liver fatty acid binding protein mRNA level, measured by Norther n blot analysis and cytosolic content of this protein, analyzed by imm unoblotting, increased concurrently. From these results we conclude th at the increase in the cytosolic liver fatty acid binding protein leve l by bezafibrate is due to an enhancement of the transcription rate of the liver fatty acid binding protein gene. Whether the transcriptiona l effect is mediated by peroxisome proliferator-receptor remains to be elucidated.