黑色素是一種由許多有機物質構成的一種異質聚合物，其廣泛的分佈在動物體表及體內的許多器官。在過去的一些研究當中，含有黑色素的細胞被認為是保護動物體避免紫外光傷害以及皮膚癌的重要角色。黑色素的保護機制一部分來自於它對可見光波段具有寬廣的吸收帶，在生物體中扮演著光屏蔽的作用，另一方面黑色素也被認為其具有一些更微觀的機制來清除細胞環境中的自由基或是活性氧。在此研究中，我們使用從烏賊萃取出的黑色素顆粒加入至人體的Retinal Pigment Epithelial (RPE) 細胞中，將此做為實驗組，無外加黑色素顆粒者為對照組，在外加過氧化氫來控制活性氧起始濃度的狀況下，將這些細胞培養在一個可提供外部光源照光的自製培養箱內來進行實驗。此研究中使用計數玻片來計算細胞的存活率，以及活性氧指示劑和螢光顯微鏡來做活性氧定量的量測。透過比較細胞存活率以及活性氧含量隨時間的結果顯示，以光來激發黑色素可以清除細胞環境中的活性氧，增加細胞的存活率。 Melanin is a heterogeneous biological polymer widespread in our skin and body tissue.Some research reports that melanocytes have a key role in protecting our skin from the damaging effects of UV radiation and in preventing skin cancer. Furthermore, Melanin is believed that it serves as a photo-protective role in vision by absorbing light and a scavenger of free radicals and reactive oxygen species (ROS). Heterogeneous melanin aggregates from Sepia officinalis, a species of cuttlefish, were added to cultured human retinal pigment epithelial (RPE) cells. Cultures in a home-made incubator were continuous irradiated by a illuminator with controlling the initial concentration of ROS by adding hydrogen peroxide.Cell viability were performed by hemacytometer and the quantity of intracellular ROS were measured by the use of DCFH-DA, a ROS indicator and fluorescence microscope. Time-dependent measurement of cell viability and ROS were performed on parallel cultures consisting of RPE cells which evenly divided into two cultures, one added Sepia melanin and one containing only native melanin. These experiments conclusively demonstrate that melanin serves as a light-activated ROS scavenger to increasing cell viability.
