Increased Prostaglandin Response to Oxytocin in Ewes Fed a Diet High in Omega‐6 Polyunsaturated Fatty Acids

Abstract

Diets high in omega-6 polyunsaturated fatty acids (n-6) are associated with increased prostaglandin F(2α) (PGF(2α)) synthesis in cattle, however, the specific effects on the potential prostaglandin response to an oxytocin challenge in sheep have not been reported. The aim of the current study was to determine whether oxytocin-stimulated PGF(2α) was significantly increased when ewes were fed a diet high in n-6 compared with a control diet low in n-6. Merino x Border Leicester ewes (n = 30) received one of two dietary treatments, either high in n-6 (70 % oat grain) or low in n-6 (control diet, 100 % cereal/legume silage). Ewes consumed the diets for 44 days prior to two consecutive oxytocin challenges. Plasma n-6 and PGF(2α) metabolite (PGFM) concentrations following oxytocin challenge were greater (P < 0.05) when ewes were fed a diet high in n-6 compared with the control diet. A higher availability of n-6 may have lead to an increased in vivo synthesis of PGF(2α), however, further research is required to determine the exact mechanisms involved.

The Role of Neurotransmitters in Protection against Amyloid-β Toxicity by KiSS-1 Overexpression in SH-SY5Y Neurons

“…Both in vivo adminstration and in vitro administration of oxytocin [65, 66] or vasopressin [67, 68] causes an activation of prostaglandin synthesis that is cyclooxygenase dependent. The SH-SY5Y neuronal cell line is known to express the vasopressin gene [69] suggesting that this could be a source of the endogenous material antagonized by atosiban.…”

Linoleic Acid Increases Prostaglandin E2 Release and Reduces Mitochondrial Respiration and Cell Viability in Human Trophoblast-Like Cells

“…Specifically, exposure to elevated concentrations of palmitic acid induces inflammatory responses through reactive oxygen species (ROS) production in human placental trophoblast cells [29]. Further, in sheep, consumption of a diet with elevated concentrations of LA increases circulating maternal prostaglandin concentrations [30]. In human primary trophoblasts, there is significant reduction in mitochondrial respiration with increasing maternal obesity [31].…”

The analysis of lamb and beef fatty acids with a 30 m BPX70 column is comparable with a 120 m column

“…A number of fatty acid indices considered important for human health outcomes were calculated. The arachidonic acid (C20:4n-6) to eicosapentaenoic acid (C20:5n-3, ARA:EPA) ratio indicates the relative availability of precursors for PGF 2α and PGE 2 , respectively (Gulliver et al, 2013); the DHA de ciency index (DHADI), calculated from the ratio of C22:5n-6 to C22:4n-6, which indicates a relative de cit of DHA accompanied by an increased conversion of C22:4n-6 to C22:5n-6 (Neuringer et al, 1986, van den Ham et al, 2001; the DHA Su ciency Index (DHASI), calculated from the ratio of C22:6n-3 to C22:5n-6, which indicates a relative de ciency of DHA relative to the longest LCn-6PUFA DPAn-6 (Hoffman and Uauy, 1992, Hornstra and De Vriese, 2003); the PUFA to SFA ratio (P:S Ratio) which indicates a relative abundance of healthy fatty acids and reduced risk of CVD (Singer et al, 1986) and the Essential Fatty Acid Status Index (EFI), calculated from the ratio of (n-3 PUFA + n-6 PUFA) to (n-7 MUFA + n-9 MUFA) which indicates a relative availability of essential fatty acids (Al et al, 1995, de Groot et al, 2004, Hornstra et al, 1992. In addition, the ratio of C18:2n-6 (LA) to C18:3n-3 (ALA) was also determined (LA:ALA).…”