Study on Superoxide Dismutase Activity in Scar Tissues / 대한피부과학회지

ABSTRACT

BACKGROUND: Superoxide disrnutase(SOD) provides a protective defease mechanism against potential cytotoxicity of superoxide radical in the aerobic organism. Although human skin is constantly at risk for developing acute and chronic changes by ultraviolet radiation and phototoxic reactions with exogenous and endogenously procluced photosensitizing molecules, studies in SOD in the human skin are rare. OBJECTIVE: We measured the level of SOD activities in the scar tissues and the normal human skin specimens. This study was to investigate changes of SOD activity by age, sex, and regional differences of SOD activities in the scar issues and the normal skin. METHODS: Aut,hors assayed the level of SOD activit,ies in 32 scar tissues(male 8, female 24) and 11 normal human skin specimens(male 8, female 3), which were obtaine 3 from face/neck(17 and 3 specimens), forearm(only 4 scar tissues), trunk(10 and 8 specimens), and lower extremity(only 1 scar tissue). RESULTS: First, activities of total SOD, Cu, Zn-SOD, and Mn-SOL ere 18.93+5.49, 16.97+55.31, and 1.96+0.90 units/mg proteiii respectively in the scar tissues. Second activities of total SOD, Cu, Zn-SOD, and Mn-SOD were 17.27+7.09, 13.82+6.44, and 3.45+1.07 units/mg protein respectively in the normal skin. Third, the changes of total SOD, Cu, Zn-SOD, and Mn-SOD activities by age and sex were similar each other and three were no significant, differneces between age groups in total, Cu, Zn- SOD, and Mn-SOD activities. Fourth, in sun exposed area and unexposed area there were no significant differences in the scar tissues in SOD activities. But, SOD activite.(total, Cu, Zn, and Mn-SOD) in face/neck were higher than those in trunk and lower extremity in tae normal skin(P<0.05). CONCLUSION: These findings suggest that there are no differences in the intrinsic SOD activities by age and sex in the mature scar tissues and the normal skin. Differences between exposed and unexposed area in the normal skin are due to the induction of exogenous SOD activity by sun-light generation of superoxide radicals. In wound, increased production of leukocyte derived superoxide radicals is the main factor of increased level of SOD activity.