The Effects of Low-level Light Irradiation on Human Dermal Fibroblasts and Monocytic U-937 Cells

• Main Authors: Ju-Ai Feng, 馮如愛
• Other Authors: Wen-Ting Li
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/86061887100390268645

碩士 === 中原大學 === 醫學工程研究所 === 94 === After the theory of photomodulation was proposed, light therapy has been widely used in clinical treatments, particularly in wound healing. Lately, light emitting diodes (LEDs) have gradually replaced lasers and became new generation of light sources in the light therapy. Here we describe the effects of red-light irradiation on different ways of culturing human dermal fibroblasts (HDFs) and human lymphoma cells (U-937) by using the optimal stimulating parameters obtained previously. The LEDs used had a wavelength of 630 nm. Its irradiance was 15 mW/cm2 and the radiant exposure was 4 J/cm2. The change in cell numbers was analyzed by direct cell counting. Significant enhancement of HDFs proliferation was found after light irradiation. The growth of HDFs was also promoted by incubating HDFs in the culture supernatant of illuminated U-937 cells. The secretion of total collagen by HDFs was estimated by using Sirius red- Fast green stain. The increase of the collagen secretion by HDFs was observed after irradiation. The secretion of collagen was also enhanced by incubating HDFs in the supernatant of light-stimulated U-937 cells. By using DCFDA analysis for the generation of reactive oxygen species (ROS) by HDFs, no significant difference was observed after illumination.