Ampelopsin inhibits H₂O₂-induced apoptosis by ERK and Akt signaling pathways and up-regulation of heme oxygenase-1.

Oxidative stress plays an important role in neurodegenerative disorders. Ampelopsin, a flavonoid abundant in Rattan tea (Ampelopsis grossedentata), is a potent antioxidant and its neuroprotective effect against H₂O₂-induced apoptosis in PC12 cells is investigated here for the first time. It was found that treatment of cells with ampelopsin for 1 h significantly reduced the loss of vitality, LDH release and apoptosis and inhibited the formation of reactive oxygen species (ROS). Ampelopsin was able to prevent the activation of p38 induced by H₂O₂. In addition, up-regulation of heme oxygenase-1 (HO-1) expression by ampelopsin was shown to be both dose- and time-dependent. Mechanically, HO-1 expression induced by ampelopsin was found to be due to activation of the ERK and Akt signaling pathways, because it was almost completely blocked by the specific inhibitors of ERK and Akt. These results suggest that ampelopsin increases cellular antioxidant defense through activation of the ERK and Akt signaling pathways, which induces HO-1 expression and thereby protects PC12 cells from H₂O₂-induced apoptosis.