Figure 4. Melatonin protected N2a cells from PrP106-126-induced mitochondrial dysfunction. Fluorescence was detected by flow cytometry (FACS) analysis of ROS production (A, B) and JC-1 as a marker of mitochondrial membrane potential (MMP) (C, D) in N2a cells after treatment. The horizontal axis shows the FITC. (E) ATP levels. *P < 0.05, **P < 0.01, ***P < 0.001. All experiments were repeated at least three times.