Collagen production in diabetic wounded fibroblasts in response to low-intensity laser irradiation at 660 nm

Background: Collagen type I (Col-I) is a major component of the extracellular matrix and is important in wound healing processes. Several studies have shown that low-intensity laser irradiation (LILI) biostimulates Col-I synthesis both in vitro and in vivo. This study aimed to determine if LILI affects collagen production and related cellular responses in an in vitro diabetic wounded fibroblast model. Materials and Methods: This study was performed on isolated human skin fibroblasts. Different cell models (normal and diabetic wounded) were used. Cells were irradiated with 5 J/cm² at a wavelength of 660 nm and incubated for 48 or 72 h. Nonirradiated cells (0 J/cm²) were used as controls. Cellular viability (Trypan blue exclusion test), morphology (bright-field microscopy), proliferation [VisionBlue™ quick cell proliferation assay and 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide assay], and Col-I (enzyme-linked immunoabsorbent assay) were assessed. Results: Diabetic wounded cells irradiated with 5 J/cm² at 660 nm showed a significant increase in cell migration, viability, proliferation, and collagen content. Conclusions: This study shows that LILI stimulates Col-I synthesis in diabetic wound healing in vitro at 660 nm.