Adiponectin gene polymorphisms are associated with long-chain ω3-polyunsaturated fatty acids in serum phospholipids in nondiabetic Koreans

Abstract

CONTEXT: Hypoadiponectinemia is caused by interactions between genetic and environmental factors, including the quality of dietary fats.

OBJECTIVE: We investigated the association of single-nucleotide polymorphisms (SNPs) in the adiponectin gene (ADIPOQ) with dietary fat intake or fatty acid (FA) composition in serum phospholipids, plasma adiponectin, and insulin resistance.

METHODS: Nondiabetic subjects (n = 1194) were genotyped for three ADIPOQ SNPs (-11377C>G; 45T>G; 276G>T) after screening of eight sites. Dietary fat intake, FA composition in serum phospholipids, adiponectin, and homeostasis model assessment of insulin resistance (HOMA-IR) were also measured.

RESULTS: The 276G carriers (n = 1082) showed lower high-density lipoprotein cholesterol (P = 0.024) and adiponectin (P < 0.001) but higher glucose (P = 0.015) and HOMA-IR (P = 0.005) than 276T/T subjects (n = 112). No associations were found in other SNPs. After adjusted for age, sex, body mass index, and the proportion of 18:2ω6 and 18:3ω3 (biomarkers of long term essential FA intake), the 276G carriers showed lower proportions of total ω3FA (P = 0.026), 20:5ω3 (P = 0.021), and 22:5ω3 (P = 0.024) in serum phospholipids. Among FAs in serum phospholipids, 18:2ω6 highly correlated with ω3-polyunsaturated FA (PUFA) intake (r = 0.260, P < 0.001) and adiponectin (r = 0.150, P < 0.001). The 276G carriers with a higher proportion of 18:2ω6 (≥12.5%) exhibited more pronounced characteristics, i.e. lower adiponectin (P < 0.001), lower high-density lipoprotein cholesterol (P = 0.004), higher HOMA-IR (P = 0.013), and lower long-chain ω3PUFAs (20:5ω3, 22:5ω3, and 22:6ω3, P < 0.001). Additionally, the effect of 276G>T on the relationship between adiponectin and HOMA-IR was modified by 18:2ω6 proportion.

CONCLUSION: ADIPOQ 276G is associated with reduced proportion of long-chain ω3PUFAs in serum phospholipids in nondiabetic Koreans