Fig. 6

ICA targeted Nrf2 in glial cells to produce DA neuroprotection. Primary rat midbrain neuron-enriched and neuron-glia cultures were pretreated with ICA (0.1 μM) for 30 min followed by 6-OHDA (40 μM) stimulation for 7 days. TH protein expression was measured by western blot analysis (a). Primary mixed-glia in transwells were treated with Nrf2-siRNA (40 nM) for 24 h and the silence rate was verified by real-time RT-PCR and western blotting (b). Then, mixed-glial cells after silence were transferred to neuron-enriched cultures. After that the reconstituted neuron-glia co-cultures were treated with ICA and 6-OHDA for 7 days. DA neurons quantification was determined by immunocytochemical staining and western blotting with anti-TH antibody (c and d). Results were mean ± SEM from 3 independent experiments performed in triplicate. *p < 0.05 compared with the control cultures, ^#p < 0.05 compared with 6-OHDA-treated cultures, ^△p < 0.05 compared with 6-OHDA+ICA-treated cultures. Scale bar = 100 μm