POLYUNSATURATED FATTY-ACID REGULATION OF HEPATIC GENE-TRANSCRIPTION

Polyunsaturated fatty acids (PUFA) modulate the rate of gene transcrip tion for a number of different genes including hepatic lipogenic and g lycolytic genes, adipose Glut-4 and stearoyl-CoA desaturase and interl eukins. Some of the transcriptional effects of PUFA appear to be media ted by eicosanoids, but the PUFA suppression of lipogenic and glycolyt ic genes is independent of eicosanoid synthesis and appears to involve a nuclear mechanism directly modified by PUFA. With the recent clonin g of a fatty acid-activated nuclear factor termed peroxisome-prolifera tor-acitivated receptor (PPAR) has come the suggestion that PPAR may b e the PUFA response factor. However, this review presents several line s of evidence that indicate that the PPAR and PUFA regulation of gene transcription involves separate and independent mechanisms, and the PP AR is not the PUFA response factor.