Chronic exposure of the skin to sunlight causes damage to the underlying connective tissue with a loss of elasticity and firmness. Silicon (Si) was suggested to have an important function in the formation and maintenance of connective tissue. Choline- stabilized orthosilicic acid (“ ch- OSA” ) is a bioavailable form of silicon which was found to increase the hydroxyproline concentration in the dermis of animals. The effect of ch- OSA on skin, nails and hair was investigated in a randomized, double blind, placebo- controlled study. Fifty women with photodamaged facial skin were administered orally during 20 weeks, 10 mg Si/day in the form of ch- OSA pellets (n=25) or a placebo (n=25). Noninvasive methods were used to evaluate skin microrelief (forearm), hydration (forearm) andmechanical anisotropy (forehead). Volunteers evaluated on a virtual analog scale (VAS, “ none=0, severe=3” ) brittleness of hair and nails. The serum Si concentration was significantly higher after a 20- week supplementation in subjects with ch- OSA compared to the placebo group. Skin roughness parameters increased in the placebo group (Rt: + 8% ; Rm: + 11% ; Rz: + 6% ) but decreased in the ch- OSA group (Rt: - 16% ; Rm: - 19% ; Rz: - 8% ). The change in roughness from baseline was significantly different between ch- OSA and placebo groups for Rt and Rm. The difference in longitudinal and lateral shear propagation time increased after 20 weeks in the placebo group but decreased in the ch- OSA group suggesting improvement in isotropy of the skin. VAS scores for nail and hair brittleness were significantly lower after 20 weeks in the ch- OSA group compared to baseline scores. Oral intake of ch- OSA during the 20 weeks results in a significant positive effect on skin surface and skin mechanical properties, and on brittleness of hair and nails.
Objective: To quantitatively examine the dynamics of molecular alterations in volved in dermal remodeling after carbon dioxide (CO2) laser resurfacing of phot odamaged human skin. Design: Serial in vivo biochemical analyses after laser therapy. Setting: Academic referral center, Department of Dermatology, University of Mich igan, Ann Arbor. Subjects: Volunteer sample of 28 adults, 48 to 76 years old, wi th clinically evident photodamage of the forearms. Intervention: Focal CO2 laser resurfacing of photodamaged forearms and serial biopsies at baseline and variou s times after treatment. Main Outcome Measures: Reverse transcriptase real-tim e polymerase chain reaction technology and immunohistochemistry were used to ass ess levels of type I and type III procollagens; matrix metalloproteinases (MMPs) 1, 3, 9, and 13; tropoelastin; fibrillin; primary cytokines interleukin 1β an d tumor necrosis factor α ; and profibrotic cytokine transforming growth factor β 1. Results: Production of type I procollagen and type III procollagen messen ger RNA peaked at 7.5 and 8.9 times baseline levels, respectively, 21 days after treatment and remained elevated for at least 6 months. Increases in messenger R NA levels of several cytokines (interleukin 1β , tumor necrosis factor a, and t ransforming growth factor β 1) preceded and/or accompanied changes in collagen levels. Marked increases in messenger RNA levels of MMP- 1 (39 130- fold), MMP - 3 (1041- fold), MMP- 9 (75- fold) , andMMP- 13 (767- fold)were noted. Le vels of fibrillin and tropoelastin rose in a delayed fashion several weeks after treatment. Conclusions: The biochemical changes seen after CO2 laser resurfacin g proceed through a well-organized and highly reproducible wound healing respo nse that results in marked alterations in dermal structure. These quantitative c hanges may serve as a means for comparison as other therapeutic modalitiesmeant to improve the appearance of photodamaged skin are evaluated.
