title: Changes in plasma metabolites and glucose homeostasis during omega-3 polyunsaturated fatty acid supplementation in women with polycystic ovary syndrome.
abstract: BACKGROUND
  Both fish (FO) and flaxseed oils (FLX) are n-3 polyunsaturated fatty acids (PUFA). Fish oil contains long chain while FLX contains essential n-3 PUFA. We demonstrated that FO altered insulin secretion and resistance in polycystic ovary syndrome (PCOS) women but FLX did not. Surprisingly, the effects of FO were similar to those of the n-6 PUFA-rich soybean oil (SBO). Since increased branched chain (BCAA) and aromatic amino acids (AA) affect insulin secretion and resistance, we investigated whether FO, FLX and /or SBO affect plasma metabolites, especially AA.
  
  
  RESULTS
  In this six-week, randomized, 3-parallel arm, double-blinded study, 54 women received 3.5 g/day FO, FLX or SBO. In 51 completers (17 from each arm), fasting plasma metabolites were measured at the beginning and at the end. As compared to FLX, FO and SBO increased insulin response and resistance as well as several BCAA and aromatic AA. Pathway analysis indicated that FO exerted the largest biochemical impact, affecting AA degradation and biosynthesis, amine, polyamine degradation and alanine, glycine, l-carnitine biosynthesis and TCA cycle, while FLX had minimal impact affecting only alanine biosynthesis and l-cysteine degradation.
  
  
  CONCLUSIONS
  Effects of FO and SBO on plasma AA were similar and differed significantly from those of the FLX. The primary target of dietary PUFA is not known. Dietary PUFA may influence insulin secretion and resistance directly and alter plasma AA indirectly. Alternatively, as a novel concept, dietary PUFA may directly affect AA metabolism and the changes in insulin secretion and resistance may be secondary.
authors.affiliation: The University of California at Davis, Department of Internal Medicine, Division of Endocrinology, Clinical Nutrition and Vascular Medicine, Davis, CA, United States; Department of Veterans Affairs Northern California Health Care System, Mather, CA, United States.
authors.forename: Sidika E
authors.initials: SE
authors.lastname: Karakas
authors.affiliation: University of California at Davis Genome Center, Davis, CA, United States.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Perroud
authors.affiliation: University of California at Davis Genome Center, Davis, CA, United States.
authors.forename: Tobias
authors.initials: T
authors.lastname: Kind
authors.affiliation: University of California at Davis Genome Center, Davis, CA, United States.
authors.forename: Mine
authors.initials: M
authors.lastname: Palazoglu
authors.affiliation: University of California at Davis Genome Center, Davis, CA, United States.
authors.forename: Oliver
authors.initials: O
authors.lastname: Fiehn
keywords: Branched chain amino acids; Insulin resistance; PCOS; Plasma metabolites; n-3 Polyunsaturated fatty acids