Suppression of nitric oxide implicated in the protective effect of echinacoside on H2O2-induced PC12 cell injury.

We investigated whether suppression of nitric oxide (NO) implicated in the protective effect of echinacoside (ECH), a phenylethanoid glycoside, on H2O2-induced injury to the rat pheochromocytoma cell line (PC12 cells). Data show that application of ECH to H2O2-injured PC12 cells (HIPCs) increased cell viability and decreased the necrotic ratio. Laser scanning confocal microscopic (LSCM) analysis suggested that ECH exerted an inhibitory effect on the formation of NO. In addition, RT-PCR analysis revealed that ECH down-regulated p65 and iNOS mRNA expressions in HIPCs. In summary, suppression of NO is related to the protective effect of ECH on HIPCs.