Figure 1: Effect of SKP-SCs on cell viability and autophagy in SH-SY5Y cells under 6-OHDA intervention. Control group: Normal SH-SY5Y cells; 6-OHDA group: SH-SY5Y cells were pretreated with 50 μM 6-OHDA. (A, B) Double immunofluorescence intensities of LC3B (green, Alexa Fluor-488) or p62 (green, Alexa Fluor-488) and TH (red, Alexa Fluor-647) in SH-SY5Y cells. The immunofluorescence intensities of LC3B and p62 were increased in the 6-OHDA group compared with control group. Scale bars: 20 μm. (C, D) After pretreatment with Con-CM or SKP-SC-CM for 4 hours, SH-SY5Y cells were cultured with 50 μM 6-OHDA for 12 hours. Bands of α-syn, TH, LC3B, and p62 detected by western blot assay. (E–H) Quantitative results of α-syn, TH, LC3B, and p62 expression. Data are presented as the mean ± SEM. Relative protein expression was fold to control group. The experiments were repeated three times. *P < 0.05, **P < 0.01, ***P < 0.001 (one-way analysis of variance followed by Tukey’s post hoc test). 6-OHDA: 6-Hydroxydopamine; Con-CM: control conditioned medium; LC3B: microtubule-associated protein 1 light chain 3; p62: sequestosome 1; SKP-SC-CM: skin-derived precursor-Schwann cells conditioned medium; TH: tyrosine hydroxylase; α-syn: α-synuclein.