Induction of apoptosis by fractional CO 2 laser treatment

Introduction: Fractional CO2-laser is considered a preferential method for skin resurfacing, but little is known about the molecular mechanisms underlying this surgical tool. In the present study, we investigated the possible role of apoptosis by the sequential analysis of lesional skin after laser treatment, with special attention to power. Moreover, we have analyzed if there is a correlation with clinical improvement. Materials and methods: We evaluated the effects of fractional CO2-laser in twelve patients with photodamage skin Fitzpatrick types I to III. Apoptosis markers were assessed by an immunohistochemical study on skin samples of foream at 24 h, 72 h and 7 days after the irradiation with 15 W or 20 W. Moreover, clinical improvement was assessed by iconography. Results: Fractional CO2-laser induced an inflammatory repair process mediated by activation of apoptotic pathway that was completed in 7 days. The expression of proapototic markers, as annexin-VII and Caspases-9 was increased 2472 hours after irradiation and decreased after 7 days. While the expression of the anti-apototic marker Bcl-2 increased progressively during 7 days after treatment. Conclusion: Our study suggests that the skin's appearance may be enhanced by creating skin changes through apoptosis. Apoptosis, one of the major mechanisms of cell death, might play a key role in initiating the paracrine cascades that lead to cell proliferation. © 2012 Informa UK, Ltd.