Sunbed use induces the photoaging-associated mitochondrial common deletion.

Sunbeds have become very popular and, as a result, health effects of their use are of growing concern. In this regard, exposure to ultraviolet radiation from sunbeds may cause premature skin aging. Evidence for this assumption, however, has thus far been elusive. In this study, we assessed whether sunbed use induced the generation of a large-scale mitochondrial DNA mutation in human skin, the so-called Common Deletion, which is well known to be photoaging-associated. Fifty-nine individuals who voluntarily started to use sunbeds were observed over 3 months. Punch biopsies were taken from neck and buttock skin before the first and after their last sunbed visit. The Common Deletion content was determined by quantitative real-time PCR. Multiple linear regression analysis was performed for statistical analysis. Volunteers without previous sunbed use showed a 2.56-fold increase (95% CI: 0.97-6.78) of the Common Deletion in neck and a 3.58-fold increase (95% CI: 1.44-8.89) of the Common Deletion in buttock skin samples after sunbed use. Participants with previous sunbed use showed no increase. This study indicates that sunbed use may contribute to mtDNA deletion-associated skin photoaging.

Ultraviolet-free phototherapy.

BACKGROUND: Ultraviolet (UV) radiation phototherapy has been used for decades in the management of common skin diseases. On the other hand, UV radiation is a complete carcinogen and as a consequence, UV phototherapy is usually not used for the long-term management of children and young adults and in combination with topical or systemic immunosuppressants. PURPOSE: The therapeutic effectiveness of a new UV-free irradiation device in the treatment of patients with atopic hand and/or foot eczema was studied. METHODS: In a single-blinded trial 10 patients with atopic hand and/or foot eczema were treated with a sham irradiation device and with the new developed UV-free irradiation device DermoDyne during the following 4 weeks. All irradiation's lasted 30 min per treatment three times weekly. RESULTS: UV-free irradiation was found to induce a significant clinical improvement of atopic hand and foot eczema (P = 0.0001) in marked contrast to the sham-irradiation (P = 0.39). CONCLUSION: Our studies demonstrate that visible light can be successfully used for the treatment of patients with atopic eczema.