ABSTRACT
The suppression of hepatic lipogenesis by dietary polyunsaturated fatty acids appears to require that the fatty acid contain a minimum of 18-carbons and two double bonds in the 9 and 12 positions, and at least one of these bonds must be of the cis configuration. The classic studies of Chattoff and his colleagues had indicated that fat ingestion would suppress acetate incorporation into hepatic lipids. This chapter suggests that polyunsaturated fats were better acute inhibitors of hepatic fatty acid synthesis and malonyl-Co A accumulation than were saturated fats. Loss of one of the double bonds by hydroxylation renders the fatty acid inactive. However, a fatty acid may contain additional double bonds and still retain inhibitory potency. The strongest argument against the idea that fatty acid membrane compositional changes are responsible for the control of gene expression lies in the kinetics of transcriptional inhibition vs. membrane fatty acid changes.
