Fig. 1.

Effects of MPP⁺ and ethanol extract of Periplaneta americana L. (PAE) on SH-SY5Y cell viability. A The cell viability of SH-SY5Y incubated with different concentrations of MPP⁺ ranging from 50 μM to 1000 μM for 48 h. B The cell viability of SH-SY5Y treated with different concentrations of PAE for 48 h. C Cells were pretreated with different concentrations of PAE for 2 h followed by incubation with 500 μM MPP⁺ for another 48 h. Cell viability was expressed as the percentage of the viability of the control group. D Cells were pretreated with different concentrations of PAE for 2 h followed by incubation with or without MPP⁺ (500 μM) for another 48 h, apoptotic cells were evaluated by hoechst staining, bar = 100 μm. E Quantification of apoptotic cells. Data are presented as mean ± SD (n = 3), ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, ^****p < 0.0001, vs. control group, ^#p < 0.05, ^##p < 0.01, ^###p < 0.001, ^####p < 0.0001, vs. MPP⁺ treated group