Polyunsaturated fatty acids differentially alter PGF 2α and PGE 2 release from bovine trophoblast and endometrial tissues during short-term culture

Abstract

Two studies tested the hypothesis that eicosapentaenoic (20:5ω3; EPA), docosahexaenoic acids (22:6ω3; DHA) or linoleic acid (C18:2ω6; LIN) reduced bovine endometrial and trophoblast prostaglandin F 2α (PGF 2α) and prostaglandin E 2 (PGE 2) release during short-term culture. In Study 1, endometrial tissues were collected from non-lactating, non-pregnant cows and endometrial plus trophoblast tissues from pregnant cows 16 days post-insemination. In Study 2, endometrial and trophoblast tissues were collected on day 17 of pregnancy, from cows synchronised using a double prostaglandin (PG) or Ovagen™ synchronisation. Tissues were incubated in medium only (M) or media supplemented with fatty acids: eicosapentaenoic (20:5ω3; EPA), docosahexaenoic acids (22:6ω3; DHA) or linoleic acid (C18:2ω6; LIN). In Study 1, PGE 2 release from ‘pregnant’ endometria was higher ( P = 0.094) than from ‘non-pregnant’ endometria, while PGF 2α concentrations were similar. Fatty acids treatment had no effect on PGF 2α or PGE 2 release from either pregnant or non-pregnant endometria. Individual fatty acid treatments had no effect on the ratio of PGF 2α to PGE 2 from trophoblast tissues, but when the data from the 3 fatty acid treatments were combined (EPA, DHA and LIN treatment groups) the ratio of PGF 2α to PGE 2 was reduced ( P = 0.026) when compared to medium only. In Study 2, PGE 2 concentrations were higher ( P = 0.013) from the trophoblast collected from Ovagen™ cows as compared to that of the PG synchrony group. When the data from the 3-omega fatty acids were combined (DHA and EPA treatment groups), the 3-omega treatments decreased ( P < 0.05) PGE 2 biosynthesis from both endometrial and trophoblast tissues from animals synchronised following PG synchrony but not Ovagen™ synchrony. Short-term culture with low concentrations of 3-omega fatty acids tended to reduce prostaglandin release from trophoblast collected 16 days after insemination, with the type of synchrony modifying PGE 2 production from the trophoblast tissues collected 17 days after insemination. The ability of exogenous fatty acids to modify embryonic prostaglandin release needs to be examined in the context of supplementing dairy cows with different sources of fats. Synchronisation method altered trophoblast PGE 2 release, highlighting the importance of the hormonal environment in modifying embryonic prostaglandin synthesis and release.