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Photoaging accounts for most age-related changes in skin appearance. It has been suggested that both astaxanthin, a potent antioxidant, and collagen hydrolysate can be used as antiaging modalities in photoaged skin. However, there is no clinical study using astaxanthin combined with collagen hydrolysate. We investigated the effects of using a combination of dietary astaxanthin and collagen hydrolysate supplementation on moderately photoaged skin in humans. A total of 44 healthy subjects were recruited and treated with astaxanthin (2 mg/day) combined with collagen hydrolysate (3 g/day) or placebos, which were identical in appearance and taste to the active supplementation for 12 weeks. The elasticity and hydration properties of facial skin were evaluated using noninvasive objective devices. In addition, we also evaluated the expression of procollagen type I, fibrillin-1, matrix metalloproteinase-1 (MMP-1) and -12, and ultraviolet (UV)-induced DNA damage in artificially UV-irradiated buttock skin before and after treatment. The supplement group showed significant improvements in skin elasticity and transepidermal water loss in photoaged facial skin after 12 weeks compared with the placebo group. In the supplement group, expression of procollagen type I mRNA increased and expression of MMP-1 and -12 mRNA decreased compared with those in the placebo group. In contrast, there was no significant difference in UV-induced DNA damage between groups. These results demonstrate that dietary astaxanthin combined with collagen hydrolysate can improve elasticity and barrier integrity in photoaged human facial skin, and such treatment is well tolerated. [ABSTRACT FROM AUTHOR]

Background: Narrow-band (TL-01) UVB lamps are being increasingly used for phototherapy in cases of psoriasis and other dermatoses due to the excellent results obtained. However, in Korea many patients receiving phototherapy have complained about the tanning effect of ultraviolet radiation., Objective: The aim of this study was to determine the time-course of pigmentation induced by phototherapy during and after narrow-band UVB treatment., Methods: Changes in skin color were recorded during phototherapy in 40 patients and after treatment in 20 patients. All patients were Korean and were evaluated during 10 weeks of phototherapy (three sessions per week), and then weekly post-phototherapy using two different reflectance spectrophotometers for 10 weeks. Results are presented as erythema (E)- and melanin (M)-indexes and as L*a*b* values as recommended by the Commission Internationale de l'Eclairge and individual typology angle (ITA)., Results: L* values, which indicate luminance, decreased continuously over the 5 weeks of phototherapy and showed a plateau after 5 weeks of treatment, and then slowly recovered over 10 weeks of post-treatment observation. Patterns of a* and b* values were comparable with L* values both during and after therapy. Mean ITA values also showed a pattern similar to L* values. E and M indexes changed slowly both during and post-phototherapy. In addition, when data were analyzed by skin type, the different skin types showed temporal patterns similar to the overall skin values, but the L* values and ITA and M indexes of skin type III recovered faster than those of skin types IV or V., Conclusion: This study shows that pigmentation induced by narrow-band UVB phototherapy increases continuously during the therapy and that recovery requires 10 weeks or more.