Regulation of prostaglandin F(2alpha) biosynthesis by long chain fatty acids in cattle

A series of in vitro experiments and an in vivo experiment were conducted to examine the effects of long-chain fatty acids (LCFA) on PGF2alpha biosynthesis in cattle. Treatment of bovine endometrial (BEND) cells with phorbol 13, 14-dibutyrate (PDBu) resulted in induction of PGF2alpha secretion. The PDBu-induced PGF 2alpha secretion coincided with increased PGHS-2 mRNA and protein expression. There was no evidence for PDBu modulation of PPARdelta mRNA or protein synthesis in cultured BEND cells.;Priming of BEND cells with ST, LNA, and EPA reduced PGF2alpha response to PDBu by 17%, 14%, and 66%, respectively. Both saturated and unsaturated fatty acids had no detectable effects on PGHS-2, PGES or PPARdelta mRNA response to PDBu. Similarly, supplementation of BEND cells with cis-9, trans-11 or trans-10, cis-12 CLA isomers greatly decreased PGF2alpha response to PDBu. Co-incubation with both CLA isomers increased PGHS-2 and PPARdelta mRNA abundance in PDBu-stimulated BEND cells, suggesting that these fatty acids alter PGF2alpha production through a mechanism that does not require repression of PGHS-2 or PPARdelta gene expression. Priming of BEND cells with cis-9, trans-9, cis-11, and trans-11 isomers of octadecenoic acid further enhanced PGF2alpha and PGHS-2 mRNA response to PDBu. Pre-incubation of BEND cells with cis and trans monounsaturated fatty acids decreased PGES mRNA response to PDBu. None of the fatty acids studied altered PPARdelta mRNA or protein levels.;Feeding trans fatty acids to primiparous or multiparous Holstein cows did not induce any significant alterations in production or metabolic responses when compared to supplementation with saturated fatty acids. Dietary supplementation of cows with tFA significantly increased plasma PGFM concentration within the first week of lactation. Whether this augmentation in PGF2alpha production results in improved fertility and immune competency warrants further research.