A cross-sectional PCOS cohort (n = 104) was included and plasma fatty acid profiles were analyzed. Effects of LC n-3 PUFA supplementation on fasting and postprandial metabolic and hormonal markers were determined in PCOS subjects (n = 22) by a randomized, crossover, placebo-controlled intervention. Direct effects of n-6 (omega-6) compared with n-3 PUFAs on steroidogenesis were investigated in vitro in primary bovine theca cells. Crosssectional data showed that a greater plasma n-6 PUFA concentration and n-6:n-3 PUFA ratio were associated with higher circulating androgens and that plasma LC n-3 PUFA status was associated with a less atherogenic lipid profile. Supplemenation of LC n-3 PUFA reduced plasma bioavailable testosterone concentrations (P < 0.05), with the greatest reductions among subjects who exhibited greater reductions in plasma n-6:n-3 PUFA ratios. Notably, the treatment of bovine theca cells with n-6 rather than with n-3 PUFAs up-regulated androstenedione secretion (P < 0.05). Arachidonic acid modulates androstenedione secretion, which suggests an inflammatory mechanism in the hormonal perturbment of PCOS and an indirect effect of n-3 PUFAs through the displacement of n-6 PUFAs. (Am J Clin Nutr. 2011 Mar;93(3):652-62.) PMID: 21270384.
