Skin exposure to ultraviolet B (UVB) irradiation leads to the generation of reactive oxygen species (ROS). Excessive ROS cause aging of the skin via basement membrane/extracellular matrix degradation by matrix metalloproteinases (MMPs). We recently demonstrated that 3-bromo-4,5-dihydroxybenzaldehyde (BDB), a natural compound of red algae, had a photo-protective effect against UVB-induced oxidative stress in human keratinocytes. The present study focused on the effect of BDB on UVB-irradiated photo-aging in HaCaT keratinocytes and the underlying mechanism. BDB significantly impeded MMP-1 activation and expression, and abrogated the activation of mitogen-activated protein kinases and intracellular Ca2+ level in UVB-irradiated HaCaT cells. Moreover, BDB decreased the expression levels of c-Fos and phospho-c-Jun and the binding of activator protein-1 to the MMP-1 promoter induced by UVB irradiation. These results offer evidence that BDB is potentially useful for the prevention of UVB-irradiated skin damage.

中文翻译：

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红藻化合物3-Bromo-4,5-dihydroxybenzaldehyde保护人类角质形成细胞免受氧化应激相关分子和UVB辐射激活的途径。

皮肤暴露于紫外线B（UVB）辐射会导致产生活性氧（ROS）。过多的ROS通过基质金属蛋白酶（MMP）通过基底膜/细胞外基质降解引起皮肤老化。我们最近证明了3-溴-4,5-二羟基苯甲醛（BDB），一种红藻的天然化合物，对人角质形成细胞中UVB诱导的氧化应激具有光保护作用。本研究集中于BDB对HaCaT角质形成细胞中UVB照射的光老化的影响及其潜在机理。BDB显着阻碍了MMP-1的激活和表达，并废除了UVB照射的HaCaT细胞中有丝分裂原激活的蛋白激酶的激活和细胞内Ca2 +的水平。而且，BDB降低了c-Fos和磷酸化c-Jun的表达水平以及激活剂蛋白1与UVB辐射诱导的MMP-1启动子的结合。这些结果提供了证据，表明BDB可能对预防UVB照射的皮肤损害有用。