Anthocyanins and their gut metabolites reduce monocyte adhesion and migration across TNFa-activated endothelial cells trough nutrigenomic mechanisms regulating endothelial permeability
Résumé
Cardioprotective effects of dietary anthocyanins are partly attributed to their ability to maintain
endothelial function. However, the underlying mechanisms of action are not fully understood. This study
aimed to test the effect of anthocyanins and their gut metabolites, at physiologically-relevant conditions,
on endothelial cell function and decipher the underlying molecular mechanisms of action using
integrated omics approaches.
Primary endothelial cells were treated with a mix of 0.1μM cyanidin-3-arabinoside, 0.1μM cyanidin-3-
galactoside, 0.1μM cyanidin-3-glucoside, 0.1μM delphinidin-3-glucoside, 0.1μM peonidin-3-glucoside
and 0.5μM 4-hydroxybenzaldehyde for 3h or with a mix of gut metabolites: 0.2μM protocatechuic, 2μM
vanillic, 1μM ferulic and 2μM hippuric acids for 18h. Additionally, successive treatment with both mixes
mimicked the anthocyanin pharmacokinetics following their dietary intake. Endothelial cell dysfunction
was induced using TNFa and monocytes added to asses adhesion and transmigration. Gene and
miRNA expression, signaling protein phosphorylation and molecular docking were investigated.
All mixes significantly reduced monocyte adhesion and transendothelial migration by 24.5% and 46.2%
in average. Gene expression analysis using TLDA arrays showed that mixtures modulated the
expression of genes involved in cell-cell adhesion, cytoskeleton organization or focal adhesion.
Bioinformatic analyses were done to identify potential transcription factors involved in the observed
nutrigenomic effects and signalling proteins regulating their activity. Western blot analysis showed the
ability of tested compounds to modulate phosphorylation of NfkB-p65 or p38 signalling proteins.
Docking identified 25 out of 63 potential cell signaling proteins to which these compounds can bind to
and initiate the observed nutrigenomic effect. The mixes also affected miRNA expression. Bioinformatic
analysis showed that more than half of modulated miRNAs are involved in regulation of endothelial cell
permeability, contributing to the observed changes in endothelial cell function.
Integration of these results revealed endothelial-protective properties of anthocyanins and their gut
metabolites and deciphered new underlying multi-target and multi-layered mode of action.