Narrow-band red LED light promotes mouse hair growth through paracrine growth factors from dermal papilla.

摘要

Sevaral clinical reports [1-3] have suggested that hair growth is promoted by low-level laser therapy (LLLT), defined as therapy using red-beam or near-infrared laser with a wavelength of600-1100 nm and an output power of 1-500 mW, since Mester et al. [4] reported effect of LLLT on hair growth in 1967. However, the irradiation area of laser system is small, and most systems are expensive and relatively immobile. On the other hand, light emitting diode (LED) light has many advantages related to safety and superior portability compared to UV and laser therapies, because they are low-coherent, quasi-monochromatic and non-thermal. We developed a new narrow-band LED (Mignon belle LT-1 Crystalline by MIGNON BELLE CO., LTD., Osaka, Japan), and utilized this red LED (638 nm with half band width 3 nm) to explore its effect on hair growth of mice.