Chung J H, Youn S H, Koh W S, Eun H C, Cho K H, Park K C, Youn J I
Department of Dermatology, Seoul National University College of Medicine, Korea.
J Invest Dermatol. 1996 Apr;106(4):715-20. doi: 10.1111/1523-1747.ep12345608.
Ultraviolet (UV) B radiation may trigger cutaneous inflammatory responses by directly inducing epidermal keratinocytes to elaborate specific cytokines such as interleukin (IL-1) and IL-6. Because IL-1 is a potent inducer of IL-6, one may speculate that the release of IL-6 by keratinocytes after UV exposure is mediated via the release of IL-1 in an autocrine or paracrine manner. We demonstrated that UVB irradiation upregulated IL-1 alpha mRNA at a lower dose (15 mJ/cm2) and then downregulated IL-1 alpha mRNA expression at high doses (30-40 mJ/cm2). The kinetic profile of IL-1alpha mRNA expression showed a biphasic response, with the early increase by 1 h after UV exposure and the secondary increase at 6 h after UV. On the other hand, the expression of IL-6 mRNA was increased with increasing doses of UVB (0-45 m/J/cm2) and showed a single peak at 6 h post UV. These results may indicate that UVB radiation could regulate the expression of IL-1alpha and IL-6 mRNA in keratinocytes by different mechanisms. Our data show that anti-human IL-1alpha antibody inhibits UV-induced IL-6 production and mRNA expression in cultured keratinocytes. The addition of recombinant IL-1alpha to the medium increased IL-6 synthesis and augmented IL-6 production and mRNA expression in cultured human keratinocytes by UVB irradiation. These results support the hypothesis that UVB irradiation-enhanced IL-6 production and mRNA expression may be mediated by IL-1alpha.
紫外线B辐射可通过直接诱导表皮角质形成细胞产生特定细胞因子（如白细胞介素-1（IL-1）和IL-6）来引发皮肤炎症反应。由于IL-1是IL-6的强效诱导剂，因此有人推测紫外线照射后角质形成细胞释放IL-6是通过自分泌或旁分泌方式释放IL-1介导的。我们发现，低剂量（15 mJ/cm2）紫外线B照射可上调IL-1α mRNA表达，而高剂量（30 - 40 mJ/cm2）照射则下调IL-1α mRNA表达。IL-1α mRNA表达的动力学曲线呈现双相反应，紫外线照射后1小时出现早期增加，紫外线照射后6小时出现二次增加。另一方面，IL-6 mRNA表达随紫外线B剂量增加（0 - 45 mJ/cm2）而升高，并在紫外线照射后6小时出现单峰。这些结果可能表明紫外线B辐射可通过不同机制调节角质形成细胞中IL-1α和IL-6 mRNA的表达。我们的数据表明，抗人IL-1α抗体可抑制紫外线诱导的培养角质形成细胞中IL-6的产生和mRNA表达。向培养基中添加重组IL-1α可增加IL-6合成，并增强紫外线B照射后培养的人角质形成细胞中IL-6的产生和mRNA表达。这些结果支持以下假说：紫外线B照射增强的IL-6产生和mRNA表达可能由IL-1α介导。
