APOE e4 Is Associated with Postprandial Inflammation in Older Adults with Metabolic Syndrome Traits

The apolipoprotein E (APOE) polymorphism impacts blood lipids and biomarkers of oxidation and inflammation, contributing to an isoform-dependent disease risk. We investigated the effect of the APOE genotype on postprandial metabolism after consumption of three different isoenergetic (4200 kJ) meals in older adults with a CVD risk phenotype. In a randomized crossover study, participants with metabolic syndrome traits (APOE E3, n = 39; E4, n = 10; mean age, 70 & PLUSMN; 5 years; BMI 31.3 & PLUSMN; 3.0 kg/m(2)) consumed a Western-like diet high-fat (WDHF), Western-like diet high-carbohydrate (WDHC), or Mediterranean-like diet (MED) meal. Parameters of lipid and glucose metabolism, inflammatory, and oxidative parameters were analyzed in blood samples collected at fasting and 1-5 h postprandially. Data were analyzed by linear mixed models. The magnitude of the IL-6 increase after the WDHF meal was significantly higher in E4 than in E3 carriers (iAUC: E4 = 7.76 vs. E3 = 2.81 pg/mL x h). The time to detect the IL-6 increase was shorter in the E4 group. All meals produced postprandial glycemia, insulinemia, and lipidemia, without differences between the E3 and the E4 groups. IL-1 beta and oxidized LDL levels did not change postprandially. In conclusion, APOE E4 carriers display increased postprandial inflammation, indicated by higher postprandial IL-6 increase, when compared to non-carriers.

Automated summary

In this study, it was found that APOE E4 carriers exhibit increased postprandial inflammation, as indicated by a higher postprandial IL-6 increase compared to non-carriers. Other parameters of metabolism did not show significant differences, suggesting a specific impact of the APOE genotype on postprandial inflammatory response.