Figure 8.

Influence of quercetin on PI3K/Akt pathways and ROS formation. Quercetin is a potent inhibitor of PI3K/Akt and an important trigger for formation of reactive intermediates, such as o‐semoquinone, quercetin–quinone products (QQ), and other forms ROS. Both PI3K inhibition and reactive intermediates formed from degradation of quercetin contribute to quercetin‐induced cell death. However, stabilization of quercetin with ascorbic acid (AA) paradoxically reduces apoptosis, but enhanced efficacy of quercetin‐induced PI3K inhibition.