Fig. 3.

Potential role of polyphenolic compounds in the formation of Systemic Inflammatory Response (SIR). Having entered the alimentary canal, polyphenolic compounds are absorbed into the bloodstream. All phenolic compounds can scavenge reactive oxygen (ROS) and nitrogen (RNS) species due to their structural peculiarities. Thus they can prevent initial influence of ROS and RNS on redox-sensitive transcriptional factors in the cell. Flavonoids, stilbenes, coumarins and tannins exert most of their influence through SIRT1 or SIRT6, thus inhibiting NFκB and STAT signalling, while inducing Nrf2 signalling. Phenolic acids, stilbenes, coumarins and tannins can directly inhibit STAT signalling. All phenolic compounds are potent activators of Nrf2. Flavonoids and phenolic acids additionally inhibit NFκB through IκBα. Some of phenolic acids and flavonoids can also inhibit NFκB activation through non-canonical (NIK) pathway. Note: Pa – phenolic acids; Fl – flavonoids; St – stilbenes; Cu – coumarins; Ta – tannins.