Bioaccessibility, bioavailability, and anti-inflammatory effects of anthocyanins from purple root vegetables using mono- and co-culture cell models

Scope: Immune-inflammatory signaling and metabolic effects are the main pillars for bioactivity of anthocyanins derived from highly pigmented root vegetables. This study aims to assess the bioaccessibility and bioavailability of purple carrot and potato derived anthocyanins and the molecular mechanisms of their ability to ameliorate cellular inflammation in a mono- and co-culture cell models. Methods and results: An in vitro gastrointestinal model was used and demonstrated bioaccessibility of 44.62 and 71.8% for anthocyanins of purple carrot and potato, respectively. These accessible anthocyanins significantly inhibited cellular inflammation in Caco-2 cells. Intact cyanidinglycoside or petunidinglycoside (respectively from carrots and potatoes) were transported across a transmembrane cell model and detected by LC-MS/MS. Computational docking and glucose uptake analyses suggested uptake of anthocyanins was mediated by hexose transporters. Subsequent experiment using an inflamed Caco-2 BBe1/THP-1 co-culture cell model showed these transported anthocyanins inhibited IL-8 and TNF-alpha secretion,and expression of pro-inflammatory cytokines by blocking NF-kappa B, and MAPK mediated inflammatory cellular signaling cascades, but with varying degrees due to structural features. Conclusion: Anthocyanins from purple carrots and potatoes possess a promising anti-inflammatory effect in model gut system. They can be absorbed and act differently but are in general beneficial for inflammation-mediated diseases.