Pseudoginsenoside-F11 Protects against Transient Cerebral Ischemia Injury in Rats Involving Repressing Calcium Overload

Abstract

Calcium overload has been reported to trigger neuronal death following stroke. Pseudoginsenoside-F11 (PF11), an ocotillol-type ginsenoside with various neuroprotective activities, has displayed therapeutic efficacy against permanent ischemic stroke. The present study examined the protective potential of PF11 in rats subjected to 2-h transient middle cerebral artery occlusion (tMCAO) and in cultured primary cortical neuron (PCN) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R). Single intravenous administration of PF11 (12 mg/kg) significantly reduced infarct volume, brain edema, neurological deficit and cortex neuron loss at 24 h after reperfusion. Immunoblotting and immunofluorescence demonstrated that PF11 inhibited the over activation of μ-Calpain and the reduction of calcium calmodulin kinase II-α, reduced the degradation of sarcoplasmic/endoplasmic reticulum ATPase-2 and alleviated endoplasmic reticulum stress (ERS) in tMCAO rats. What's more, rats treated with PF11 (12 mg/kg) intravenously immediately after reperfusion, and then intraperitoneally every 24 h for 14 days exhibited lessened cortex neuron loss, reduced mortality and improved performances of rotarod, grip strength and gait patterns at 1, 4, 7, and 14 days after tMCAO. Furthermore, in vitro investigations showed PF11 increased cell viability, reduced neurites decline, restored ATP level and decreased calcium content in cultured PCN under OGD/R. Moreover, PF11 alleviated ERS, reversed the diminished levels of NMDA-2B subunit, postsynaptic density protein 95 and neuronal nitric oxide synthase both in vivo and in vitro. Our study indicates that PF11 produced neuroprotection and improved long-term outcomes while repressing calcium overload in model of transient focal ischemia, suggesting that PF11 might be a considerable candidate for stroke treatment.

Keywords: calcium overload; cerebral ischemia; endoplasmic reticulum stress; neuronal nitric oxide synthase; pseudoginsenoside-F11; μ-calpain.