PARP1 and Parkinson disease: Moreover, the pro-PARP-1 level was decreased (p < 0.05; Supplementary Figure 4(b)), but the level of cleaved-PARP-1 (p < 0.001; Supplementary Figure 4(c)) along with the cleaved/pro-PARP-1 ratio (p < 0.001; Figure 6(d)) was increased in the ROT-induced PD model in SH-SY5Y cells.