Polydatin protects neuronal cells from hydrogen peroxide damage by activating CREB/Ngb signaling

Oxidative stress-induced neuronal cell death contributes significantly to the physiological processes of a number of neurological disorders. Polydatin (PD) has been reported to protect against Alzheimer's disease (AD), ischemic stroke and traumatic brain injury. However, the underlying neuroprotective mechanisms remain to be elucidated. The current study suggested that PD activates AKT/cAMP response element-binding protein (CREB) signaling and induces neuroglobin (Ngb) to protect neuronal cells from hydrogen peroxide (H(2)O(2)) in vitro. PD inhibited the H(2)O(2)-induced neuronal cell death of primary mouse cortical neurons and N2a cells. Functional studies showed that PD attenuated H(2)O(2)-induced mitochondrial dysfunction and mitochondrial reactive oxygen species production. Mechanistically, PD was verified to induce the phosphorylation of AKT and CREB and increase the protein level of Ngb. The luciferase assay results showed that Ngb transcriptional activity was activated by CREB, especially after PD treatment. It was further indicated that PD increased the transcription of Ngb by enhancing the binding of CREB to the promoter region of Ngb. Finally, Ngb knockdown largely attenuated the neuroprotective role of PD against H(2)O(2). The results indicated that PD protected neuronal cells from H(2)O(2) by activating CREB/Ngb signaling in neuronal cells, indicating that PD has a neuroprotective effect against neurodegenerative diseases.