Inhibition of NF- κB activity by minor polar components of extra-virgin olive oil at gastric level.

The present work evaluates the effect of olive oil phenols on NF-κB activity in human gastric adenocarcinoma cells. The total phenol content was measured by the Folin Ciocalteu method, whereas the composition was assessed by LC-MS/MS analysis. Secoiridoids represented 71% and 83% of the Italian and Spanish extracts, respectively, phenol alcohols were in the range 9-13%. Ligustroside aglycone was the most abundant (37% and 46%, respectively, in the Italian and Spanish sample), and the concentration of flavonoids AP and LU was below 1%. Phenol extracts were assayed at 0.25-7.5 µg/mL, whereas single compounds were at 0.5-25 µM. Both the extracts inhibited the NF-κB driven transcription in a concentration-dependent manner: IC(50) for the Italian and the Spanish extract were 0.86 and 1.28 µg/mL, respectively. The IC(50) for individual compounds ranged from 4.5 to 13 µM. All the compounds under study inhibited nuclear translocation as well. The data suggest that consumption of extra-virgin olive oil may be beneficial for preventing the onset of gastric inflammation leading to more serious diseases.