Puerarin Protects Human Neuroblastoma SH-SY5Y Cells against Glutamate-Induced Oxidative Stress and Mitochondrial Dysfunction

Glutamate, the principal excitatory neurotransmitter, plays a central role in brain metabolism; however, aberrant neurotransmission of glutamate has been linked to neurodegenerative diseases. Therefore, the effective agents that target at glutamate-induced cell injury will be useful for prevention and treatment of neurodegenerative diseases. In this study, the neuroprotective effect of puerarin, an active isoflavone extracted from the Chinese herb Radix puerariae, against glutamate-induced cell injury in human neuroblastoma SH-SY5Y cells was evaluated for the first time. The results showed that the pretreatment of puerarin could attenuate glutamate-induced cell injury in a dose-dependent manner. This protective effect was mediated through inhibiting reactive oxygen species generation, attenuating the upregulation of Bax and downregulation of Bcl-2, preserving mitochondrial membrane potential (MMP), preventing cytochrome c release, and reducing caspase activity. These findings may significantly contribute to a better understanding of the neuroprotective effect of puerarin and provide new insights into its application toward neurodegenerative diseases in the future.