title: N-3 polyunsaturated fatty acid DHA during IVM affected oocyte developmental competence in cattle.
abstract: The positive effect of n-3 polyunsaturated fatty acids (FAs) on fertility in ruminants seems to be partly mediated through direct effects on the oocyte developmental potential. We aimed to investigate whether supplementation with physiological levels of docosahexaenoic acid (DHA, C22:6 n-3 polyunsaturated fatty acids) during IVM has an effect on oocyte maturation and in vitro embryo development in cattle. We reported that DHA (0, 1, 10, or 100 μM) had no effect on oocyte viability or maturation rate after 22-hour IVM. Incubation of oocyte-cumulus complexes with 1-μM DHA during IVM significantly increased (P < 0.05) oocyte cleavage rate as compared with control (86.1% vs. 78.8%, respectively) and the greater than 4-cell embryo rate at Day 2 after parthenogenetic activation (39.1% vs. 29.7%, respectively). Supplementation with 1 μM DHA during IVM also induced a significant increase in the blastocyst rate at Day 7 after IVF as compared with control (30.6% vs. 17.6%, respectively) and tended to increase the number of cells in the blastocysts (97.1 ± 4.9 vs. 81.2 ± 5.3, respectively; P = 0.08). On the contrary, 10-μM DHA had no effects, whereas 100-μM DHA significantly decreased the cleavage rate compared with control (69.5% vs.78.8%, respectively) and the greater than 4-cell embryo rate at Day 2 after parthenogenetic activation (19.5% vs. 29.7%). As was shown by real-time polymerase chain reaction, negative effects of 100-μM DHA were associated with significant increase of progesterone synthesis by oocyte-cumulus complexes, a three-fold increase in expression level of FA transporter CD36 and a two-fold decrease of FA synthase FASN genes in cumulus cells (CCs) of corresponding oocytes. Docosahexaenoic acid at 1 and 10 μM had no effect on expression of those and other key lipid metabolism-related genes in CC. In conclusion, administration of a low physiological dose of DHA (1 μM) during IVM may have beneficial effects on oocyte developmental competence in vitro without affecting lipid metabolism gene expression in surrounding CCs, contrarily to 100 μM DHA which diminished oocyte quality associated with perturbation of lipid and steroid metabolism in CC.
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France; IFCE, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France.
authors.forename: Mouhamad
authors.initials: M
authors.lastname: Oseikria
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France; IFCE, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France. Electronic address: Sebastien.Elis@tours.inra.fr.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Elis
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France; IFCE, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Maillard
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France; IFCE, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Corbin
authors.affiliation: INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France; CNRS, UMR 7247 Physiologie de la Reproduction et des Comportements, Nouzilly, France; Université François Rabelais de Tours, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France; IFCE, UMR Physiologie de la Reproduction et des Comportements, Nouzilly, France.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Uzbekova
mesh_terms: D000818:Animals; D002417:Cattle; D054885:Cumulus Cells / Q000378:metabolism; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D047108:Embryonic Development / Q000187:drug effects*; D059471:In Vitro Oocyte Maturation Techniques; D050356:Lipid Metabolism / Q000187:drug effects; D009865:Oocytes / Q000187:drug effects* / Q000254:growth & development; D011374:Progesterone / Q000378:metabolism
chemical_list: D004281:Docosahexaenoic Acids; D011374:Progesterone
keywords: Cumulus; Gene expression; IVM; Oocyte competence; n-3 PUFA