Comparing the cytotoxic effect of light-emitting and organic light-emitting diodes based light therapy on human adipose-derived stem cells

Abstract

Light has attracted significant attention as a promising tool in the biomedical and cosmetic industries. However, little is known about the cytotoxic effects of conventional light sources based on their physical effects such as temperature and luminance. Here, the cytotoxic effects of representative light sources, a light-emitting diode (LED) and an organic light-emitting diode (OLED), were studied with human adipose-derived stem cells (hADSCs). Regardless of the identical light energy conditions, LED group induced a higher apoptotic activity in hADSCs than the OLED group due to its significant heat generation compared to OLED as further demonstrated with heat shock protein family gene expression. Additionally, we further confirmed the effect of luminance by irradiating light from LED and OLED under the same temperature and energy conditions. Increased cell proliferation was confirmed in the OLED group, and a significant expression of intracellular reactive oxygen species was observed in the LED group without showing heat shock protein upregulation. Taken together, the differences in cytotoxicity and cellular response after LED irradiation compared with OLED irradiation can be varied with temperature and lumi-nance control. This study suggests that OLED based device could be an alternative and promising light source for future biomedical and cosmetic applications. (c) 2021 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.