Plasma metabolites mediate the association of coarse grain intake with blood pressure in hypertension-free adults
Xin Liu Nutrition, Metabolism and Cardiovascular Diseases: August 2020 (Volume 30, Issue 9)
Highlights
• Metabolomic profiles predicting blood pressure were identified in young adults without hypertension.
• Coarse grain intake was inversely associated with metabolomic profiles of blood pressure.
• Mediating effect of metabolites on the coarse grain intake–blood pressure association were determined.
Background and aims
Increased intake of whole/coarse grains was associated with improved blood pressure control, but concurrent metabolism alterations are less clear. We sought to identify metabolomic profiles of blood pressure, and to explore their mediation effects on the coarse grain intake-blood pressure association among young adults free of hypertension.
Methods and results
Plasma metabolome of 86 participants from the Carbohydrate Alternatives and Metabolic Phenotypes study was characterized by untargeted lipidomics and metabolomics using liquid chromatography–high-resolution mass spectrometry. We identified 24 and 117 metabolites associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP), respectively, using random forest modeling and partial correlation analysis. Moreover, metabolite panels for highly specific prediction of blood pressure (8 metabolites for SBP and 11 metabolites for DBP) were determined using ten-fold cross-validated ridge regression (R 2 ≥ 0.70). We also observed an inverse association between metabolite panel of SBP ( β ± SE = −0.02 ± 0.01, P = 0.04) or DBP ( β ± SE = −0.03 ± 0.01, P = 0.02) and coarse grain intake. Furthermore, we observed significant mediating effects of metabolites, in particular, sphingolipid ceramides, on the association between coarse grain exposure and blood pressure using both bias-corrected bootstrap tests and high-dimensional mediation analysis adapted for large-scale and high-throughput omics data.
Conclusions
We identified metabolomic profiles specifically associated with blood pressure in young Chinese adults without diagnosed hypertension. The inverse association between coarse grain intake and blood pressure may be mediated by sphingolipid metabolites.