Grape seed proanthocyanidins protect PC12 cells from hydrogen peroxide-induced damage via the PI3K/AKT signaling pathway

Grape seed proanthocyanidins (GSP) are natural Flavonoids with strong antioxidant and anti-apoptotic effects. Oxidative stress and neuronal Apoptosis are major contributors to spinal cord injury (SCI). In this study, we assessed the potential protective effects of GSP on hydrogen peroxide (H₂O₂)-damaged pheochromocytoma-12 (PC12) cells in an in vitro model of SCI as well as the putative mechanism of action. We established a model using PC12 cells with oxidative damage induced by H₂O₂. Cells were treated with various concentrations of GSP (control group, 200 μmol/L H₂O₂ group, 5 μM GSP + H₂O₂ group, 10 μM GSP + H₂O₂ group, and 25 μM GSP + H₂O₂ group). The CCK-8 assay was used to determine cell activity. Dichloro-dihydro-fluorescein diacetate was used to detect intracellular Reactive Oxygen Species (ROS), and flow cytometry was used to determine Apoptosis rate. Western blot analysis was used to detect the expression of Caspase-3, Bax, Bcl-2, and PI3K/Akt proteins. The results showed that GSP reduced H₂O₂-induced intracellular ROS and inhibited Apoptosis. Furthermore, GSP inhibited the expression of Caspase-3 and Bax, while promoting the expression of Bcl-2. In addition, GSP promoted the phosphorylation of PI3K and Akt. Moreover, a PI3K Inhibitor (LY294002) weakened the protective effects of GSP on H₂O₂-induced PC12 cells. In conclusion, GSP pretreatment can protect PC12 cells from oxidative damage induced by H₂O₂ via the PI3K/Akt signaling pathway.