Perfluorodecanoic acid enhances the formation of oleic acid in rat liver

Abstract

The feeding of perfluorodecanoic acid (PFDA) to male rats at a dietary concentration of 0.005% (w/w) for 7 days resulted in a marked increase in the activity of microsomal stearoyl-CoA desaturation in the liver. This increase in the overall desaturation activity was due to the induction of terminal desaturase among the components comprising the desaturation system. In contrast, PFDA inhibited desaturation in vitro, seemingly due to interference with electron transport through the desaturation system. Accordingly, PFDA can be an inducer and also an inhibitor of delta9-desaturation. PFDA feeding enhanced the conversion of radioactive stearic acid into oleic acid in the liver in vivo, indicating that the induction of delta9-desaturase by PFDA functions in vivo. PFDA feeding increased the mass of octadecenoic acid (C18:1) in the liver and the proportion of C18:1 in microsomal lipid. A highly significant linear correlation existed between the microsomal desaturase activity and the proportion of C18:1 in microsomal lipid when compared using rats in five different physiological states: control, PFDA-fed, p-chlorophenoxyisobutyric acid (clofibric acid)-fed, starved and starved/refed. These results suggest that the increase in the hepatic level of C18:1 caused by feeding of PFDA to rats can be explained by the common concept of regulation, i.e. the hepatic level of C18:1 is under the control of delta9-desaturase. The dietary administration of PFDA also increased the content of cytochrome P-450 and the activity of 7-ethoxycoumarin O-de-ethylase in the liver.

Effects of Perfluorooctanoic Acid on the Synthesis of Phospholipids in the Liver of Mice Fed a Dietary Soybean Oil, Perilla Oil or Fish Oil.

“…8) The increase in 18 : 1 and the decrease in 18 : 0 observed in the three phospholipid classes were thought to be due to an induction of stearoyl-CoA desaturase that catalyzes the conversion of 18 : 0 to 27 18 : 1. 3,7,8) It is of interest that the PFOA-induced decrease in polyunsaturated fatty acids was not significant in FO-fed mice compared to other dietary groups. This may be due to the fact that polyunsaturated fatty acids of n-3 series are preferentially utilized to form phospholipids, especially PtdEtn.…”

“…[1][2][3][4][5][6][7][8] The amounts of various phospholipids as well as triacylglycerol (TG) in the liver were greatly increased by the treatment of rats with PFOA. 2,5,8) In addition, fatty acid profile was greatly altered; octadecenoic acid (18 : 1) was increased whereas stearic acid (18 : 0) and arachidonic acid were decreased in phospholipids in rat liver.…”

“…2,5,8) In addition, fatty acid profile was greatly altered; octadecenoic acid (18 : 1) was increased whereas stearic acid (18 : 0) and arachidonic acid were decreased in phospholipids in rat liver. 3,7,8) Such changes are, at least in part, due to changes in the activities of lipid metabolizing enzymes in rat liver. [6][7][8] Compared to rats, little information is available for mice about PFOA-induced changes in lipid metabolism.…”

“…3,7,8) Such changes are, at least in part, due to changes in the activities of lipid metabolizing enzymes in rat liver. [6][7][8] Compared to rats, little information is available for mice about PFOA-induced changes in lipid metabolism. In the previous study, we demonstrated that PFOA caused a significant accumulation of TG in mice fed a diet containing soybean oil (SO) or perilla oil (PO) but not in mice fed a fish oil (FO)-containing diet.…”

Effects of 8-2 Fluorotelomer Alcohol on Oleic Acid Formation in the Liver of Rats

“…24,25) Therefore, these compounds may affect human or animal health through alterations in energy metabolism since oleic acid is a major fatty acid synthesized via de novo pathway and enriched in triglyceride. However, information is lacking about the effect of 8-2 fluorotelomer alcohol on fatty acid composition in the liver of animals.…”