Background: Red light is part of the visible light spectrum. The effects of light-emitting diode (LED)-generated red light on human skin are not well-characterized.
Objective: To study the effect of red LED-generated low-level light therapy (LLLT) on fibroblast proliferation and viability in vitro.
Methods and materials: Irradiation of normal human skin fibroblasts using red LED panels was performed in vitro, and modulation of proliferation and viability was quantified using trypan blue dye exclusion assay.
Results: Statistically significant decreases in cell proliferation were noted at the following fluences (time): 160 J/cm2 (30 minutes, 34 seconds), 320 J/cm2 (61 minutes, 07 seconds) and 640 J/cm2 (122 minutes, 14 seconds) (Figure 1). Irradiation at the 160- (98.5 ± 1.2%) and 320-J/cm2 (98.0 ± 3.1%) doses did not significantly alter viability.
Conclusion: At certain fluences, red LLLT can effectively inhibit fibroblast proliferation in vitro without altering viability and holds promise for the treatment of scars and other proliferative skin diseases.
© 2013 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.