Protective effect of senegenin on retinal ganglion cells in oxidative stress induced injury

AIM: To evaluate the effect of senegenin(Sen) on H2O2-treated retinal ganglion cells(RGCs) and to explore its underlying mechanisms.METHODS: RGCs were retrograde labeled by injection of fluorogold into the superior colliculi of SD rats on the postnatal day 3.On the postnatal days 6 to 8,the retinas were dissociated with papain and cultured.Primary RGCs cultured in vitro were treated with H2O2 and/or various doses of Sen.The viability of RGCs was evaluated by counting the fluorescence-labeled neurons under microscope.The morphological changes of the nuclei in the retinal neurons were observed by Hoechst 33258 staining.Western blotting was applied to determine the expression of cleaved caspase-3,cytochrome C and Bcl-2 in cultured retinal neurons.RESULTS: Compared with the control cells,Sen at doses of 10,20 or 40 μmol/L had no toxicity to RGCs(P0.05).However,Sen at doses of 80 and 160 μmol/L had significant toxicity to RGCs(P0.01).Compared with H2O2-injured group,Sen at doses of 10,20 and 40 μmol/L effectively protected against H2O2-induced injury in RGCs(P0.05) with the best efficiency at 40 μmol/L.Hoechst 33258 staining showed that the neuronal apoptosis caused by H2O2 was reduced by Sen.The results of Western blotting showed an up-regulation of Bcl-2,and decreased cytochrome C and cleaved caspase-3 levels by Sen in H2O2-treated retinal neurons.CONCLUSION: Sen is able to protect RGCs from H2O2-induced injury by enhancing Bcl-2 expression and inhibiting cell apoptosis.