Modulation by nutrients and drugs of liver acyl-CoAs analyzed by mass spectrometry.

The profile of liver acyl-CoAs induced by dietary fats of variable compositions or by xenobiotic hypolipidemic amphipathic carboxylates was evaluated in vivo using a novel electrospray ionization tandem mass spectrometry methodology of high resolution, sensitivity, and reliability. The composition of liver fatty acyl-CoAs was found to reflect the composition of dietary fat. Treatment with hypolipidemic carboxylates resulted in liver dominant abundance of their respective acyl-CoAs accompanied by an increase in liver fatty acyl-CoAs. Cellular effects exerted by dietary fatty acids and/or xenobiotic carboxylic drugs may be transduced in vivo by their respective acyl-CoAs.