Anti-inflammatory potential of black carrot (Daucus carota L.) polyphenols in a co-culture model of intestinal Caco-2 and endothelial EA.hy926 cells

Scope: The present study was developed to determine the ability of polyphenol-rich black carrot and its by-products, i.e., peel and pomace, to modulate the inflammatory response in tumor necrosis factor α (TNF-α) treated endothelial cells after gastrointestinal digestion and in a co-culture of intestinal Caco-2 and endothelial EA.hy926 cell model. Results: The results indicated that after 4 h of treatment, the transport of anthocyanins and phenolic acids was higher for digested samples (1.3−7%) compared to the undigested samples (0−3.3%). The transported polyphenols were able to downregulate the secretion of pro-inflammatory markers, i.e. IL-8, monocyte chemoattractant protein 1, vascular endothelial growth factor, and intercellular adhesion molecule 1, under normal and tumor necrosis factor α induced inflammatory conditions. The most pronounced protective effects were observed with digested samples under inflammatory conditions, which significantly decreased the secretion of all markers from 120−203% down to 34−144% (p < 0.001). Conclusions: Overall, these results show that the polyphenol-rich black carrot absorption products may function through an inhibitory regulation of the inflammatory cascade in endothelial cells.