반복적인 이온영동에 의한 표피 calcium gradient의 변화가 피부장벽상태에 미치는 영향

Abstract

Background: The calcium ion is important in skin barrier homeostasis. Disruption of the skin barrier increases transepidermal water loss(TEWL), and induces the loss of the epidernal calcium gradient, lamellar body(LB) secretion, epidermal lipid synthesis and epidermal DNA synthesis. Our previous research showed that iontophoresis induced the disappearance of the epidermal calcium gradient and increase in LB secretion without an increase of TEWL.

Purpose: To elucidate whether repeated changes in the epidermal calcum gradient induced by repeated iontophoresis can induce skin barrier damage, epidermal proliferation or enhance the skin barrier to irritants.

Methods: 8 to 12 week old hairless mice were used. For the group defining skin barrier damage and epidermal proliferation, iontophoresis was currented for 1h and 2h a day and repeated for 7 days. TEWL was measured at 24h after iontophoresis each day. Skin specimens were taken for measuring the epidermal thichness under light microsocope and observing the stratum corneum(SC) intercellular spaces under electron microscope. For the other group defining skin barrier enhancement to irritants, iontophoresis was currlented for 3/4h twice a day and repeated for 3 days and then 1% SLS was applied for 1h. TEWL was checked for barrier recovery rate at 15 min, 6h, 12h, 24h, 48h after the 1% SLS application.

Results: We could not find any skin barrier damage represented by TEWL, eidermal proliferation or any remarkable changes of SC intercellular spaces over the control. The barrier recovery in iontophoresis skin was accelerated at 6h, but not different after 12h compared to control skin.

Conclusion: Repeated changes of the epidermal calcium gradient without barrier damage can not induce epidermal proliferation, and repeated iontophoresis can enhance the skin barrier.