Changes in plasma metabolites and glucose homeostasis during omega-3 polyunsaturated fatty acid supplementation in women with polycystic ovary syndrome

Abstract

BackgroundBoth 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.Methods and findingsIn 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.ConclusionEffects 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.

The effect of flaxseed supplementation on body weight and body composition: a systematic review and meta‐analysis of 45 randomized placebo‐controlled trials

“…Nine of the 45 trials were performed exclusively on women and nine on men , and the remaining trials included both sexes; however, three studies did not mention sex composition of participants . Eligible studies were published between 1995 and 2016, and most of them were conducted in the USA , Canada , Iran and Brazil . The remaining studies were conducted in China , Australia , Greece , Germany , Denmark , Romania India and Japan .…”

“…Nine of the 45 trials were performed exclusively on women (31,38,41,43,45,48,51,57,75) and nine on men (40,44,46,54,56,63,65,70,74), and the remaining trials included both sexes; however, three studies did not mention sex composition of participants (58,67,68). Eligible studies were published between 1995 and 2016, and most of them were conducted in the USA (31,37,38,46,52,57,60,61,66,70,75), Canada (22,23,(41)(42)(43)48,50,67), Iran (21,59,69,71,73) and Brazil (24,39,44,45,49). Th...…”

“…Sunflower seed (38), raw rice (44), collagen (45), wheat germ (48), manioc flour (49), cassava flour (24), wheat bran (52,66) and wheat (67) were used for the control groups. Eighteen treatment arms supplemented flaxseed oil for the intervention (23, 30,31,39,40,47,50,[54][55][56][59][60][61][63][64][65]69,70,74), while the control group was provided canola oil (50,56), corn oil (54,70), olive oil (30,40,55,60), soybean oil (31,75), safflower oil (63-65), sunflower oil (23,47), MCT oil (59), n-6 oil (74) or placebo (22,39). One study used both whole flaxseed and flaxseed oil (22), and five studies used flaxseed lignan (37,41,45,51,62); the controls in these studies were assigned placebo.…”

Glucose-lowering effect of whey protein depends upon clinical characteristics of patients with type 2 diabetes

“…The underlying mechanism is that delivery of excess fatty acids along with branched chain amino acids to the mitochondria interferes with glucose utilization 30 31. In an earlier study we had demonstrated that polyunsaturated fatty acids (3 g/day) alter plasma amino acids and their metabolism in humans 32. Endogenous hypertriglyceridemia also increases fatty acid delivery to mitochondria.…”

Nutritional support and dietary interventions for women with polycystic ovary syndrome

“…16,[108][109][110][111] Mainly, most of the clinical trials of PUFA supplementation were of short duration (6-12 weeks) and the supplementation dose ranged between 2 and 4 g PUFAs per day. [108][109][110][112][113][114][115][116][117][118] A recent meta-analysis of eight clinical trials with a total of 298 females with PCOS showed a slight reduction in serum total testosterone levels following n-3 PUFA supplementation among females with PCOS, without significant impact on SHBG and DHEAS levels. 119 Results from a cross-sectional study showed that increased plasma n-6 PUFAs or increased n-6:n-3 PUFA ratio was associated with greater circulating androgen concentrations, whereas increased long-chain n-3 PUFA in plasma was associated with decreased blood lipids in women with PCOS.…”