Protective effect of paeoniflorin against glutamate-induced neurotoxicity in PC12 cells via Bcl-2/Bax signal pathway.

Paeoniflorin (PF), a monoterpene glycoside isolated from the aqueous extract of Radix Paeoniae Alba, is widely used in Traditional Chinese Medicine (TCM) for the treatment of neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). In this study, we investigated the protective mechanism of PF on glutamate-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. PC12 cells were cultured in vitro, cell viability was assessed by MTT assay, cell apoptosis as well as mitochondrial membrane potential (MMP) were detected by flow cytometric analysis and the expression profiles of apoptosis-related proteins including Bcl-2 and Bax were investigated by western blot. The results showed that PF could protect PC12 cells against glutamate-induced injury in a concentration-dependent manner and the mechanism of neuroprotective effect of PF was closely associated with up-regulation of Bcl-2 and down-regulation of Bax. It demonstrated that PF has neuroprotective effect on glutamate-induced apoptosis in PC12 cells via regulating mitochondrial membrane potential and Bcl-2/ Bax signal pathway.