Fig. 1

The effects of melatonin on cellular viability. a Cellular viability was detected via MTT assay. Melatonin had the ability to further reduce the cellular activity. b LDH content in the medium was measured to reflect the cell death in response to melatonin treatment. c, d TUNEL staining was applied to record the apoptotic rate of HeLa cell in response to TNF-α and/or melatonin treatment. e ELISA assay was used to detect the activity of caspase-3 which was used to reflect the cell death in response to TNF-α and/or melatonin treatment. f, g Western blotting was used to evaluate the expression of cleaved caspase-3 expression. *P < 0.05 vs. ctrl group, ^#P < 0.05 vs. TNF-α group