Abstract
Deep seawater (DSW) inhibits the calcification of normal human dermal fibroblasts (NHDF) caused by UVA irradiation. Previously, we reported that the expression of the alkaline phosphatase (ALP) activity of NHDF was induced on the calcification of NHDF caused by UVA irradiation and that DSW suppressed the expression of the ALP activity induced by UVA irradiation. The purpose of this study is to research the relationship between the expression of the calcification and the ALP activity of NHDF induced by UVA irradiation using DSW and two kinds of well known ALP inhibitors. In this study, electrodialyzed deep seawater (EDW) was prepared, because its evaluation was better than DSW in the irritation test using SIRC cells from rabbit cornea. First, the effect of EDW on the calcification of NHDF caused by UVA irradiation was investigated. Next, the effect of EDW on ALP activity was investigated. Furthermore, effects of etidoronic acid (ETA) and homo arginine (HA), which were well-known as ALP inhibitors, were investigated on the calcification of NHDF caused by UVA irradiation. As a result, it was suggested that the suppressive effect of these inhibitors on the calcification of NHDF caused by UVA irradiation was limited. So, the effect of the use of both EDW and an ALP inhibitor was investigated on the calcification caused by UVA irradiation at the last step in this study. As a result, the addition of both EDW and ALP inhibitors remarkably inhibited the calcification of NHDF caused by UVA irradiation. It was suggested that the addition of both EDW and ALP inhibitors has a synergistic effect on inhibition of the calcification, because this inhibitory effect on the calcification was not able to be explained by the suppressive activity on ALP activity only.
