Context/objective: Postprandial lipemia and low adiponectin represent novel risk factors for vascular disease. This study aimed to determine whether liver fat content and adiponectin are predictors of postprandial triglyceride (TG)-rich lipoproteins (TRL).
Patients/interventions: Twenty-nine men were allocated into subgroups with either low (< or =5%) or high (>5%) liver fat measured with magnetic resonance proton spectroscopy. Subjects underwent an oral fat tolerance test with measurements of postprandial TG, cholesterol, apolipoprotein B-48 (apoB-48), and apoB-100 in TRL fractions, a euglycemic hyperinsulinemic clamp, and determination of abdominal fat volumes by magnetic resonance imaging.
Results: Subjects with high liver fat displayed increased response of postprandial lipids in plasma, chylomicron, and very-low-density lipoprotein 1 (VLDL1) (Svedberg flotation rate 60-400) fractions. Liver fat correlated positively with postprandial responses (area under the curve) of TG (r = 0.597; P = 0.001), cholesterol (r = 0.546; P = 0.002), apoB-48 (r = 0.556; P = 0.002), and apoB-100 (r = 0.42; P = 0.023) in the VLDL1 fraction. Respective incremental areas under the curve correlated significantly with liver fat. Fasting adiponectin levels were inversely correlated with both postprandial lipids and liver fat content. Liver fat remained the only independent correlate in a multiple linear regression analysis for chylomicron and VLDL1 responses.
Conclusions: Liver fat content is a close correlate of postprandial lipids predicting the responses of TRL in chylomicrons and VLDL1 better than measures of glucose metabolism or body adiposity. Low adiponectin concentration is closely linked to high liver fat content and impaired TRL metabolism. High liver fat content associated with postprandial lipemia represents potential risk factors for cardiovascular disease.