Melanin plays an important role in determining skin colour. Apoptosis of melanocytes and defect in melanin production cause vitiligo. Various studies have been conducted to treat the disease, but its treatment is still difficult. Therefore, this study aimed to investigate the effect of spermidine, which is known as an inhibitor of ageing-related oxidized proteins, on melanogenesis. Even though spermidine above 50 μM had no effect on antioxidant activity and DOPA oxidation, it displayed tyrosinase activity. However, spermidine at 2000 μM was cytotoxic in B16F1 cells using MTT assay. Spermidine above 125 μM decreased the amount of intracellular hydrogen peroxide in a concentration-dependent manner in DCFH-DA analysis. It was also found that spermidine above 2000 μM increased melanin synthesis in living cells. However, spermidine above 1000 μM increased melanin synthesis in a concentration-dependent manner in H₂O₂-treated B16F1 cells. Furthermore, spermidine enhanced the expression of tyrosine hydroxylase via MITF transcription factor involved in melanogenesis in H₂O₂-treated B16F1 cells. Therefore, these results suggest that spermidine could be applied as a potential stimulator of melanin synthesis for the prevention of hair greying.

中文翻译：

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亚精胺通过 MITF 信号通路促进黑色素生成

黑色素在决定肤色方面起着重要作用。黑色素细胞凋亡和黑色素生成缺陷导致白斑病。已经进行了各种研究来治疗该疾病，但其治疗仍然很困难。因此，本研究旨在研究亚精胺（被称为衰老相关氧化蛋白的抑制剂）对黑色素生成的影响。尽管超过 50 μM 的亚精胺对抗氧化活性和多巴氧化没有影响，但它显示出酪氨酸酶活性。然而，使用 MTT 测定，2000 μM 的亚精胺在 B16F1 细胞中具有细胞毒性。在 DCFH-DA 分析中，高于 125 μM 的亚精胺以浓度依赖性方式降低细胞内过氧化氢的量。还发现高于 2000 μM 的亚精胺会增加活细胞中黑色素的合成。然而，₂ O ₂处理的B16F1细胞。此外，亚精胺通过参与 H ₂ O ₂处理的 B16F1 细胞黑色素生成的 MITF 转录因子增强酪氨酸羟化酶的表达。因此，这些结果表明亚精胺可用作黑色素合成的潜在刺激剂，以防止头发变白。