Study Of Mechanism Of Intense Pulsed Light In The Treatment Of Skin Photoaging

To study the mechanism of Intense Pulsed Light in the treatment of skin photoaging.30 SD rats were randomly divided into 3 groups:normal control group, UV group and IPL group. The rats in normal control group were fed without any intervention; the rats in UV group were radiated by UV rays; the rats in IPL group were radiated by UV rays and intense pulsed light. The histopathology of skin tissue in each groups were observed by HE dyeing. MDA, SOD, GSH-pX were detected, MMP-1,TGF-β1and bFGF were detected by western blot method.(1) The skin tissue in normal control group was characterized with integrated structure, right direction of elastic fiber and collagen fibers. While the skin tissue in UV group was characterized with un-integrated structure, degenerated fibrous tissue, chaotic arranged dermis. The skin in IPL group was damaged lightly, the structure was nearly as normal as the normal control group.(2) In UV group, the amount of MDA was significantly higher than that in the normal control group, while the amount of SOD, GSH-pX and CAT were significantly lower than that in the normal control group, P<0.05. In IPL group, the amount of MDA was significantly lower than that in the UVgroup, while the amount of SOD, GSH-pX and CAT were significantly higher than that in the UV group, P<0.05.(3) In UV group, the expression of MMP-1was significantly higher than that in the normal control group, while the amount of TGF-β1and bFGF were significantly lower than that in the normal control group, P<0.05. In IPL group, the amount of MMP-1 was significantly lower than that in the UVgroup, while the amount of TGF-Bland bFGF were significantly higher than that in the UV group, P<0.05. (1) Long time of UV irradiation could lead to skin photoaging in rats.(2) Long time of UV irradiation could induce lipid peroxidation in skin tissue, which increase the MDA amount. However, the amount of SOD, GSH-pX and CAT decreased, as well as the expression of MMP-1.(3) Intense pulsed light could improve the appearance of skin tissue which damaged by UV irradiation. It can also increase the amount of SOD, GSH-pX,CAT, and the expression of TGF-βand bFGF, and decrease the amount of MDA and the expression of MMP-1.(4) The possible mechanism of intense pulsed light in the treatment of skin photoaging may though the regulation of oxidative damage and anti- oxidative damage, and the regulation of cytokine with tissue repair function and tissue degradation.