Protective effect of Pinot noir pomace extract against the cytotoxicity induced by polycyclic aromatic hydrocarbons on endothelial cells.

Polycyclic Aromatic Hydrocarbons (PAHs) are pollutants found in the air generated mainly by the combustion of coal or biomass burning. Exposure to Polycyclic Aromatic Hydrocarbons is positively correlated with cardiovascular diseases. Phenolic compounds are widely found in the plant kingdom, and their availability from agri-food processing waste has led to an increased interest in their recovery. The production of large amounts of organic waste created by the wine industry has emphasized the valuation of these wastes to generate high-added-value by-products. The objective of this work was to investigate the protective effect of Pinot noir pomace extract on human endothelial cells against PAHs found in the polluted air of Temuco, Chile. The pomace extract was characterized by spectrophotometric analysis and high-performance liquid chromatography (HPLC). Results revealed the presence of 5 glycosylated anthocyanins and 9 low molecular weight polyphenols. Molecular docking indicated that cyanidin-3-glucoside (-9.2 kcal/mol) and quercetin (-9.6 kcal/mol) had the highest affinities for the Nrf2 binding site in the Keap1 protein, suggesting a possible competition with this transcription factor. Endothelial cells from the human umbilical vein were exposed to increasing concentrations of Phenanthrene, Fluoranthene, and Pyrene diluted in DMSO in a ratio of 3:1:1 (10 μM-200 μM). Viability through the MTS assay showed that 150 μM of PAHs was sufficient to reduce viability by 75% (p ˂ 0.0001). When the cells were pre-treated with 400 μg/ml of the extract, 150 μM of PAHs did not exert cell death (80% viability). Our preliminary results show that polyphenolic components found in Pinot noir pomace might have a beneficial effect as a protective agent.