Effects of gynosaponin TN-2 on L-DOPA-induced cytotoxicity in PC12 cells
Gynosaponins have pharmacological effects on 3,4-L-dihydroxyphenylalanine (L-DOPA)-related or dopamine-related neurological diseases; however, the neuroprotective functions of single compound of gynosaponins remain undefined. This study investigated the cytotoxic effects of gynosaponin TN-2 on L-DOPA in pheochromocytoma 12 cells. Gynosaponin TN-2, at 0.5−3 μM, did not exhibit cytotoxicity and protected against L-DOPA (100 and 200 μM)-induced cell death. Gynosaponin TN-2 (0.5 and 1.0 μM) inhibited the L-DOPA (100 and 200 μM)-induced sustained extracellular signal-regulated protein kinases 1 and 2 phosphorylation. Gynosaponin TN-2 at 0.5 and 1.0 μM also reduced L-DOPA (100 and 200 μM)-induced JNK1/2 phosphorylation and cleaved caspase-3 expression. These results suggested that gynosaponin TN-2 exerts protective effects on L-DOPA (100 and 200 μM)-induced apoptotic cell death by modulating extracellular signal-regulated protein kinases 1 and 2 activation in pheochromocytoma 12 cells.