Fig. 14
From: The progression of inorganic nanoparticles and natural products for inflammatory bowel disease
The schematic diagram summarizes the action mechanism of proanthocyanidin B2. In mice exposed to radiation, the level of oxidative stress in intestinal stem cells accumulated excessively, which led to the inactivation of Wnt signal and intestinal epithelial injury. PB2 increases the expression of antioxidant enzymes and decreases ROS levels by activating Nrf2. In addition, PB2 promotes intestinal stem cell activity by improving Wnt activation, which in turn promotes epithelial cell regeneration. In a DSS-induced colitis model, PB2 also promotes intestinal epithelial repair and reduces inflammation by reducing the nuclear localization of p65. Finally, PB2 treatment in a DSS induced colitis model chronically slowed the development of colitis-associated tumors (cited in Zhu et al. [104])