Associations of erythrocyte palmitoleic acid with adipokines, inflammatory markers, and the metabolic syndrome in middle-aged and older Chinese

Background: Palmitoleic acid has been shown to regulate adipokine expression and systemic metabolic homeostasis in animal studies. However, its association with human metabolic diseases remains controversial. Objective: We aimed to investigate associations of erythrocyte palmitoleic acid with adipokines, inflammatory markers, and metabolic syndrome (MetS) in a Chinese population. Design: Erythrocyte fatty acids were measured in a populationbased sample of 3107 men and women aged 50-70 y, for whom plasma glucose, insulin, lipid profile, adiponectin, retinol binding protein 4 (RBP-4), plasminogen activator inhibitor type 1, and highsensitivity C-reactive protein (hsCRP) were measured. MetS was defined according to the updated National Cholesterol Education Program Adult Treatment Panel III criteria for Asian Americans. Results: The mean (±SD) erythrocyte palmitoleic acid value was 0.41 ± 0.20% of total fatty acids. Palmitoleic acid was positively correlated with RBP-4 (r = 0.14, P < 0.001) and inversely correlated with adiponectin (r = 20.15, P < 0.001). After multivariable adjustment, palmitoleic acid was strongly associated with MetS and its components. ORs (95% CIs) for comparisons of extreme quartiles of palmitoleic acid were 3.50 (2.66, 4.59) for MetS, 7.88 (5.90, 10.52) for hypertriglyceridemia, 2.13 (1.66, 2.72) for reduced HDL cholesterol, 1.99 (1.60, 2.48) for central obesity, and 1.86 (1.41, 2.44) for elevated blood pressure (all P < 0.001). Further control for adipokines and hsCRP abolished the association of palmitoleic acid with central obesity but not with other MetS components. Conclusion: Erythrocyte palmitoleic acid is associated with an adverse profile of adipokines and inflammatory markers and an increased risk of MetS in this Chinese population.