Primary human keloid fibroblasts react to blue LED light irradiation with metabolic change

Aim: Blue LED light irradiation by EmoLED is currently under investigation because of its effect in wound healing improvement. In this context, several mechanisms of action are likely to occur at the same time, consistently with the presence of different light absorbers within the skin. Here we focused on evaluating the consequences of light absorption by cytochromes, since they are ubiquitous within cells. We studied fibroblasts because of their crucial role in wound healing, both in physiological conditions than in pathological ones, such as keloid scarring. Method: Human keloid tissues were excised during standard surgery and immediately underwent primary cell culture extraction. Fibroblasts were allowed to grow in the appropriate conditions and then exposed to EmoLED. A metabolic colorimetric test (WST-8) was then performed. The same experiments were also performed on 3T3 cell line. Results / Discussion: The tests revealed an effect in mitochondrial activity, which could be modulated by both the duration of the treatment and its intensity. Cell line and primary cultures experiments gave similar results, thus indicating an effect on a ubiquitous intracellular component. The metabolic changes also affects the cellular proliferation rate. Conclusion: Blue LED light affects the metabolic activity of fibroblasts. No specific effect was found on keloid fibroblasts, thus indicating a very basic intracellular component, such as cytochromes, being the target of the treatment. This also contributes to the idea that the treatment could be safely used in keloid prone patients.