Abstract: Objective To investigate the protective effect of insulin-like growth factor-1 (IGF-1) on 6-hydroxy dopamine (6-OHDA) induced oxidative damage in PC-12 cells. Methods PC12 cells were treated with 6-OHDA (concentrations of 25, 50, 100, 150 and 200 μmol/L). In order to select the optimal experimental concentration and treatment time, the activity of PC12 cells was detected by MTT at different time points of 12 h, 24 h and 48 h after treatment. PC12 cells were divided into three groups: control group, 6-OHDA group and IGF-1+6-OHDA group. The activity of PC12 cells was detected by MTT assay. Reactive oxygen species (ROS) level of PC12 cells was detected by immunofluorescence staining, and apoptosis was detected by Hoechst33342 / PI double staining method. Results With the increased concentration and the prolongation of the action time of 6-OHDA, the activity of PC12 cells decreased gradually. The concentration of 150 μmol/L and action time of 24 h of 6-OHDA were selected as the optimal experimental concentration and observation time for this study. Compared with 6-OHDA group, the activity of PC12 cells increased, the expression level of ROS and the apoptosis decreased in IGF-1+ 6-OHDA group. Conclusion IGF-1 pretreatment can reduce 6-OHDA induced oxidative damage and apoptosis of PC12 cells, also can increase cell activity, which can provide a potential strategy for the prevention and treatment of Parkinson’s disease.

Key words: insulin-like growth factor Ⅰ , hydroxydopamines, PC12 cells, oxidative stress, apoptosis, Parkinson disease, 6-hydroxy dopamine