Δ5 and Δ6 desaturase indices are not associated with zinc intake as determined by dietary assessment or modified by a zinc-FADS1 rs174547 SNP interaction in young Canadian adults. (May 2022)

• Record Type: Journal Article
• Authors: LeMoire, Ashley; Abdelmagid, Salma; Ma, David W.L.; El-Sohemy, Ahmed; Mutch, David M.
• Is Part Of: Prostaglandins, leukotrienes, and essential fatty acids. Volume 180(2022)
• Publication Date: 2022-05
• Subjects: LC-PUFA -- Delta-5 desaturase -- Delta-6 desaturase -- SNP -- Cohort study -- Zinc -- Food frequency questionnaire -- Nutrigenetics; D5D delta-5 desaturase -- D6D delta-6 desaturase -- FFQ food frequency questionnaire -- RDA recommended dietary allowance -- TNH Toronto nutrigenomics and health study; Lipids -- Periodicals; Unsaturated fatty acids -- Periodicals; Prostaglandins -- Periodicals; Leukotrienes -- Periodicals; Fatty Acids, Unsaturated -- Periodicals; Acides gras insaturés -- Périodiques; Prostaglandines -- Périodiques; Leucotriènes -- Périodiques; Lipides -- Périodiques; 612.01577
• DOI: 10.1016/j.plefa.2022.102439
• Languages: English
• ISSNs: 0952-3278

Abstract

Highlights: Zinc is a cofactor for delta-5 (D5D) and delta-6 (D6D) desaturases. Dietary zinc intake assessed by FFQ was not associated with D5D or D6D indices. The rs174547 SNP in FADS1 was associated with D5D and D6D indices. No interaction between dietary zinc intake and rs174547 was observed. Abstract: Background: Zinc is an essential trace mineral that serves as a cofactor for the delta-5 and delta-6 desaturases (D5D, D6D) that are critical for long-chain polyunsaturated fatty acid (LC-PUFA) synthesis. While plasma zinc levels are generally reported to be associated with D5D and D6D indices in humans, it remains unclear if dietary zinc intake can be similarly associated with desaturase indices. Therefore, the present investigation examined if zinc intake determined by food frequency questionnaire (FFQ) is associated with desaturase indices in young Canadian adults. Additionally, we explored whether desaturase indices were modified by an interaction between dietary zinc intake and a common variant in the FADS1 gene. Methods: Dietary zinc intake (FFQ), plasma fatty acids (gas chromatography) and the FADS1 rs174547 polymorphism were analyzed in young men and women ( n = 803) from the cross-sectional Toronto Nutrigenomics and Health Study. Product-to-precursor fatty acid ratios were used to determine desaturase enzyme indices (D5D = 20:4n-6/20:3n-6; D6D = 18:3n-6/18:2n-6). Individuals were grouped according to dietary zinc intake, as well as by their rs174547 genotype (TT vs. TC+CC). Data were analyzed by 1-way and 2-way ANCOVA. Results: Plasma fatty acids and D5D/D6D indices did not differ between individuals grouped according to dietary zinc intake. Further, the recently proposed biomarker of zinc intake, 20:3n-6/18:2n-6, was not associated with dietary zinc intake. Although the FADS1 rs174547 SNP was significantly associated with D5D and D6D indices in both men and women ( p < 0.0001), we did not find evidence of a dietary zinc intake – FADS1 SNP interaction on D5D or D6D indices. Conclusion: Dietary zinc intake, as determined using FFQs, does not predict differences in desaturase indices, irrespective of FADS1 genotype.