Ethanol Extract of Centipeda minima Exerts Antioxidant and Neuroprotective Effects via Activation of the Nrf2 Signaling Pathway

Figure 4

The active compounds EBSC-26A−EBSC-26D ameliorate oxidative stress. (a) SH-SY5Y and PC12 cells were treated with 0.5-2 μM EBSC-26A−EBSC-26D at 37°C for 24 h (upper panel) or pretreated with 0.5-2 μM EBSC-26A−EBSC-26D for 2 h and then exposed to 300 μM tBHP for an additional 6 h (lower panel); the relative viability of cells was measured by MTT assay. (b, c) SH-SY5Y cells were probed with DCFH-DA (b) and the percentage of ROS-positive cells among culture cells was quantified (c). Scale bar, 50 μm. (d) After pretreatment with 1-2 μM EBSC-26A, EBSC-26B, and vitamin E for 2 h, SH-SY5Y cells were exposed to 300 μM tBHP for an additional 6 h, and then nuclear Nrf2, HO-1, NQO-1, and SOD2 levels were detected by Western blot; β-actin was used as a loading control. (e) Relative protein levels were quantified by densitometry and normalized to Lamin B or β-actin. The results are shown as the of three independent experiments. ^# in comparison with control cells. and in comparison with the cells exposed to tBHP alone.

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