Figure 1.

Effects of increasing concentrations of melatonin on ASC viability. MTT assay on day 1 (black bars) and 7 (white bars) of culture show that no toxic effect is exerted by melatonin at the concentrations tested (0.1 to 5 µM) as compared with controls (0 µM). An increased proliferation rate of adipose-derived mesenchymal stem cells (ASCs) can be observed on day 7 for melatonin concentrations of 0.5 µM and above. Absorbance values were determined at 570 nm. Values are expressed as mean ± SD of three independent experiments. All values are referred to control ASCs after 1 day of culture. * p < 0.05 vs ASCs at the corresponding day of culture.