Activation and inhibition of nuclear factor kappa B activity by cereal extracts: role of dietary phenolic acids.

The transcription factor nuclear factor kappa B (NF-κB) plays a critical role in stress, immune, and inflammatory responses, and the modulation of its activity can be a potentially effective preventive strategy for controlling certain diseases. Cereal grains contain phenolic compounds in concentrations comparable to those in fruits and vegetables, well-known for their beneficial effect on human health. In this study we aimed to examine the effect of different phenolic extracts from barley, oat, wheat, and buckwheat on the modulation of basal and lipopolysaccharide (LPS)-induced NF-κB activity and elucidate the role of phenolic acids in this modulation. Three extracts were prepared: extracts of free phenolic compounds (M1), extracts of free phenolic acids (M2), and extracts of bound phenolic acids (HY). Generally, extracts M2 showed the highest effect on modulation of NF-κB activity with strong inhibition of LPS-induced NF-κB activity at all concentrations and of the basal NF-κB activity at concentrations ...