Differences in the wavelength-dependent photobiomodulation of monochromatic light-emitting diodes on various ocular cells

Light-emitting diodes (LEDs) have become the main source of light for various types of lighting in daily life. However, exposure to LEDs still has a potential effect on ocular cells, even at low exposure intensities. Therefore, this study explored the intracellular molecular regulatory mechanisms of monochromatic LEDs in different ocular cells. Human corneal fibroblasts (HCFs), human corneal epithelial cells (HCnEs), human conjunctival epithelial cells (HCjEs), and human lens epithelial cells (HLEs) were incubated in specific culture media supplemented with fetal bovine serum. Each cell was exposed to seven monochromatic LEDs (ranging from 360 nm to 740 nm) at 10 J/cm 2 /day for 1 day. Cell viability was analyzed via the CCK-8 reagent. A total of 60,671 genes were identified via next-generation sequencing (NGS). The potential genes were analyzed and selected via ingenuity pathway analysis (IPA) software. The screened genes were retained if the fragments per kilobase per million (FPKM) value in each cell type after exposure to either monochromatic LED was greater than 25. The number of screened genes remained at 6,907 in HCFs, 7,457 in HCnEs, 7,508 in HCjEs, and 6,696 in HLEs. According to the analysis of the FPKM values, the four cell types had different main canonical pathways before exposure to each monochromatic LED. In contrast, exposure to monochromatic LEDs affects various intracellular regulatory mechanisms, such as the cell cycle, mitochondria-mediated signals, and modifications of proteins and nucleotides, depending on the wavelength and cell type. The conclusion indicated that monochromatic LEDs trigger wavelength-dependent intracellular signaling cascades in different ocular cells. Far Eastern Memorial Hospital, Taiwan (FEMH-2018-C-004, FEMH-2024-C-049) and National Science and Technology Council, Taiwan (107-2314-B-418-011) This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.