Figure 1.

Melatonin alleviates insulin resistance (IR)-induced SH-SY5Y neuronal cell death signaling. (A) Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The mRNA levels of (B) cleaved PARP; (C) p53; and (D) Bax were measured by reverse transcription PCR. Data are expressed as mean ± standard error and each experiment included three repeats per conditions. * p < 0.05, ** p < 0.01 compared with non-stimulated control; ^φ p < 0.05 compared with insulin stimulated cells. Mel: melatonin pretreatment for 24 h before insulin stimulation.