Nonpigmented Hair Removal Using Photodynamic Therapy in Animal Model

In a study from 2016, researchers explored the use of photodynamic therapy (PDT) for the removal of nonpigmented hair in mice. The study involved BALB/c and C57BL/6 female mice and compared the effects of PDT to an 800-nm diode laser. Results indicated that PDT was effective in achieving temporary and, after multiple sessions, permanent reduction of nonpigmented hair by damaging the hair matrix and inducing a catagen-like transformation in hair follicles. In contrast, pigmented hair was less effectively removed by PDT but more effectively by laser treatment. Histological examination after repeated PDT sessions showed damage to bulge stem cells and dermal papillae, suggesting a bystander effect that could lead to permanent hair reduction. The study concluded that PDT could be a viable method for nonpigmented hair removal, while laser treatment was more suitable for pigmented hair. However, challenges remain in applying PDT to humans, including asynchronous hair cycling and potential complications with high-dose PDT.