In Vitro Effects of 1,25-Dihydroxyvitamin D3 on the Production of Interleukin-1alpha by Ultraviolet B Irradiation in Cultured Human Keratinocyte Cell Line HaCaT Cells

Chi, Doo Hyun; Lim, Yeon Soon; Jang, Kyung Ae; Sung, Hwan Tae; Yeo, Un Chul; Sung, Kyoung Jeh; Choi, Jee Ho

Abstract

BACKGROUND: Keratinocyte-derived interleukin-1(IL-1)alpha is one of the key cytokines in initiation of cutaneous inflammation. Release of IL-1alpha from human keratinocytes may be induced by proinflammatory stimuli including ultraviolet B(UVB) irradiation, and subsequently, keratinocyte-derived IL-1alpha may exert numerous paracrine and autocrine effects. 1,25-dihydroxyvitamin D3(1,25(OH)2D3) is involved in the regulation of keratinocyte proliferation and differentiation and is also recognized to have immunoregulatory properties such as an antiinflammatory effect.
OBJECTIVE
The purpose of this study was to investigate the in vitro effects of 1,25-(OH)2D3 on the production of IL-1alpha by UVB irradiation in cultured human keratinocyte cell line HaCaT cells.
RESULTS
are summerized as follows; 1. The vialility of cultured HaCaT cells measured by MTS assay at 24 hours after UVB irradiation was significantly reduced at the doses of above 100 mJ/cm2 of UVB(p<0.05). 2. The secretion of IL-1alpha by HaCaT cells was significantly increased at the doses of above 30 mJ/cm2 of UVB(p<0.05). UVB irradiation could not influence on the secretion of IL-1beta by HaCaT cells. 3. At the concentrations of 10-8M and 10-6M of 1,25(OH)2D3, the production of IL-1alpha by HaCaT cells(48 hours after 100 mJ/cm2 UVB irradiation) was significantly inhibited in both culture supernatants and cell lysates(p<0.05).
CONCLUSION
UVB irradiation increased the production of IL-1alpha by HaCaT cells and this stimulatory effect on the production of IL-1alpha induced by UVB irradiation was suppressed by 1,25-(OH)2D3. Calcipotriol(MC-903) had similar suppressive effect on the production of IL-1alpha induced by UVB irradiation in HaCaT cells to that of 1,25(OH)2D3.