Association between serum fatty acids and lipoprotein subclass profile in healthy young adults: Exploring common genetic and environmental factors

Abstract

Objective Little is known about the associations of serum fatty acids with lipoprotein profile and the underlying genetic and environmental etiology of these relationships. We aimed to analyze the phenotypic association of serum n-6 and n-3 polyunsaturated (PUFAs), monounsaturated (MUFAs) and saturated (SFAs) fatty acids (relative proportion to total fatty acids) with lipids and lipoproteins, and to quantify common genetic and environmental factors determining their covariation. Methods Two cohorts of healthy Finnish twins were assessed in young adulthood. Data were available for 1269 individual twins including 561 complete pairs. Serum metabolites were measured by nuclear magnetic resonance spectroscopy. Bivariate quantitative genetic models were used to decompose the phenotypic covariance between the pairs of traits into genetic and environmental components. Results Among the strongest correlations observed, serum total n-6 PUFAs and linoleic acid were inversely (max. r = −0.65) and MUFAs positively (max. r = 0.63) correlated with triglycerides and very low-density lipoprotein (VLDL) particle concentration, particularly with large VLDL (for n-6 PUFAs) and medium VLDL (for MUFAs). Genetic factors significantly contributed to their covariance with bivariate heritability estimates ranging from 44% to 56% for n-6 PUFAs and 58% to 66% for MUFAs. Genetic correlations with lipid traits were moderate to high (max. rA = −0.59 and 0.70 for n-6 PUFAs and MUFAs, respectively). Statistically significant, but substantially weaker phenotypic correlations of total n-3 PUFAs, docosahexaenoic acid (DHA) and SFAs with lipoprotein profile were not decomposed into their genetic and environmental components. Conclusion Shared genetic factors are important in explaining why higher concentrations of serum n-6 PUFAs and lower concentrations of serum MUFAs strongly associate with lower triglyceride and VLDL particle concentrations.

Genome-Wide Association Study for Serum Omega-3 and Omega-6 Polyunsaturated Fatty Acids: Exploratory Analysis of the Sex-Specific Effects and Dietary Modulation in Mediterranean Subjects with Metabolic Syndrome

“…No additional PUFA were reported in this platform. The results for total PUFA, omega-3, omega-6, and LA and DHA are very robust and have been validated in many publications [110][111][112][113][114][115]. Although we focused our genetic analyses on PUFA, for descriptive reasons, SFA, MUFA, and total fatty acids were also reported.…”

“…Thus, the SNP with the most significant association was rs174537 near FADS1, in determining plasma arachidonic acid (AA) concentrations (p = 5.95 × 10 −46 ). In our study, we did not analyze the association with AA, because the NMR platform used for measuring serum fatty acids [110][111][112][113][114][115][116] did not provide the separate concentration of AA. Therefore, we cannot compare the results and this is a limitation of our study in comparison with other studies providing a more comprehensive profile of fatty acids determined in other platforms (80,81,83,84,86).…”

“…Serum fatty acids were measured by proton nuclear magnetic resonance (NMR) spectroscopy as previously reported in detail [110,111]. This high-throughput NMR metabolomics platform (Nightingale Health Ltd., Helsinki, Finland), has been applied and validated in numerous studies [112,113]. The measurements of PUFA with this NMR platform were only undertaken on participants recruited at the PREDIMED Plus-Valencia field center.…”

Features of serum fatty acids in acute ischaemic stroke patients aged 50 years or older

“…Concentrations of PA, StA, and OlA were higher in the LAA_SVO group than in the CE_O group in our elderly AIS patient cohort, although patients with CE_O were not the matched controls but were ischaemic stroke patients. A previous study reported that higher concentrations of serum n-6 PUFAs and lower levels of MUFAs are strongly associated with lower TG levels [4]. However, in our study, higher concentrations of n-6 PUFAs were associated with higher TG levels.…”

“…Previous studies have reported compositions of serum fatty acids (s-FAs) such as saturated fatty acids (SFAs), n-6 polyunsaturated fatty acids (n-6 PUFAs), n-9 monounsaturated fatty acid (n-9 MUFA), and n-3 polyunsaturated fatty acids (n-3 PUFAs), and their correlation with serum lipids (s-LPs) in healthy young or middle-aged human subjects [1][2][3][4][5]. The proportion of n-6 PUFAs, as a fraction of total fatty acids, decreases with increasing age.…”