title: Altering n-3 to n-6 polyunsaturated fatty acid ratios affects prostaglandin production by ovine uterine endometrium.
abstract: Consumption of n-3 polyunsaturated fatty acids (PUFAs) is considered beneficial to health but effects on fertility remain uncertain. This study investigated the effect of n-3 PUFA supplementation on endometrial prostaglandin (PG) production. Ovine uterine endometrial cells were cultured to confluence in DMEM/F12 medium containing 10% foetal bovine serum. Stromal and epithelial cell populations were confirmed by immunocytochemistry. Cultures were supplemented with 0, 20 or 100 μM of α-linolenic acid (ALA), stearidonic acid (SDA), eicosapentaenoic acid (EPA) with lipopolysaccharide (LPS) at 0 and 0.1 μg/ml, or different combinations of EPA with arachidonic acid (AA) in serum-free medium for 24h. PGs were quantified using radioimmunoassay and PG-endoperoxide synthase (PTGS) isoforms, PGE and PGF synthase (microsomal PGES1 and PGFS) mRNAs by qPCR. LPS increased PGE2 production significantly without changing PGF2α production, causing increased PGE2:PGF2α ratios. ALA and SDA increased PGE2, PGF2α and PGE2:PGF2α ratios (P<0.05-0.01) while EPA alone did not affect PG generation. AA significantly stimulated PTGS1 and PTGS2 mRNA expression and PGE2 and PGF2α production (P<0.01). The stimulatory effect of AA was attenuated by up to 80% (P<0.05) when AA was combined with EPA. The PGE2:PGF2α ratio was not affected by AA or EPA alone, but increased when these two PUFAs were combined (P<0.05). SDA and EPA decreased PTGS1 mRNA expression (P<0.05) but did not alter PTGS2 expression. EPA and AA up-regulated mPGES1 expression (P<0.05) without affecting PGFS expression. Since AA is preferentially incorporated in uterine endometrium to produce 2-series PGs, alteration of PG production by EPA may affect many reproductive processes.
authors.affiliation: Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Herts AL9 7TA, UK. Electronic address: zcheng@rvc.ac.uk.
authors.forename: Zhangrui
authors.initials: Z
authors.lastname: Cheng
authors.forename: D Robert E
authors.initials: DR
authors.lastname: Abayasekara
authors.forename: Freya
authors.initials: F
authors.lastname: Ward
authors.forename: Daniel M W
authors.initials: DM
authors.lastname: Preece
authors.forename: Kabir A
authors.initials: KA
authors.lastname: Raheem
authors.forename: D Claire
authors.initials: DC
authors.lastname: Wathes
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D051545:Cyclooxygenase 1 / Q000235:genetics / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D004717:Endometrium / Q000187:drug effects* / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D043371:Fatty Acids, Omega-6 / Q000494:pharmacology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006911:Hydroxyprostaglandin Dehydrogenases / Q000235:genetics / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D011453:Prostaglandins / Q000378:metabolism*; D012756:Sheep / Q000235:genetics / Q000378:metabolism; D014599:Uterus / Q000187:drug effects* / Q000378:metabolism
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D008070:Lipopolysaccharides; D011453:Prostaglandins; D006911:Hydroxyprostaglandin Dehydrogenases; C031051:prostaglandin-F synthase; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2
keywords: Endometrial cells; Ewe; Polyunsaturated fatty acid; Prostaglandin-endoperoxide synthase; Prostaglandins; Uterus