College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi, 030801, PR China.
College of Veterinary Medicine, China Agricultural University, Beijing, 100193, PR China.
J Dermatol Sci. 2019 Mar;93(3):159-167. doi: 10.1016/j.jdermsci.2019.02.001. Epub 2019 Mar 12.
Pigmentation is controlled by complex mechanisms. Evidence suggests that miRNAs can regulate pigmentation. However, the mechanism has not been fully elucidated. Objective In this study, we revealed a novel mechanism that regulates pigmentation involving exosomes, miRNAs and the crosstalk between keratinocytes and melanocytes.
The expression and localization of exosome specific marker TSG101 in keratinocytes and melanocytes; Changes of melanin content in melanocytes after co-culture of exosome and melanocytes; Expression changes of target gene TYR and its related genes and inhibitory effect of miR-330-5p on pigmentation were studied by using various molecular biological techniques.
In this experiment, we used miR-330-5p in keratinocytes to verify the effect of keratinocyte derived exosome on melanocyte pigmentation. First, we found that keratinocytes secrete exosomes carrying miR-330-5p; moreover, greater miR-330-5p expression was found in exosomes derived from keratinocytes that overexpressed miR-330-5p. Second, we found that exosomes derived from keratinocytes with overexpression of miR-330-5p caused a significant increase in miR-330-5p in melanocytes. Finally, exosomes derived from keratinocytes that overexpressed miR-330-5p induced a significant decrease in the production of melanin and expression of TYR in melanocytes. Meanwhile, we overexpressed miR-330-5p in melanocytes, which also proved the inhibitory effect of miR-330-5p on pigmentation.
These findings suggest that keratinocytes crosstalk with melanocytes in the epidermal melanin unit via exosomal miRNAs. These studies reveal an important role of exosomes in melanocyte pigmentation, which opens a new pathway of melanogenesis.
色素沉着受复杂机制控制。有证据表明，miRNA 可以调节色素沉着。然而，其机制尚未完全阐明。目的 本研究揭示了一种新的调节色素沉着的机制，涉及外泌体、miRNA 以及角质形成细胞和黑素细胞之间的串扰。
检测角质形成细胞和黑素细胞中外泌体特异性标志物 TSG101 的表达和定位；共培养外泌体和黑素细胞后黑素细胞中黑色素含量的变化；采用多种分子生物学技术研究靶基因 TYR 及其相关基因的表达变化以及 miR-330-5p 对色素沉着的抑制作用。
在本实验中，我们使用角质形成细胞中的 miR-330-5p 来验证角质形成细胞衍生的外泌体对黑素细胞色素沉着的影响。首先，我们发现角质形成细胞分泌携带 miR-330-5p 的外泌体；而且，过表达 miR-330-5p 的角质形成细胞来源的外泌体中 miR-330-5p 的表达更高。其次，我们发现过表达 miR-330-5p 的角质形成细胞来源的外泌体可使黑素细胞中 miR-330-5p 显著增加。最后，过表达 miR-330-5p 的角质形成细胞来源的外泌体可诱导黑素细胞中黑色素生成和 TYR 表达显著减少。同时，我们在黑素细胞中转染 miR-330-5p，也证明了 miR-330-5p 对色素沉着的抑制作用。
这些发现表明，角质形成细胞通过外泌体 miRNA 与表皮黑素单元中的黑素细胞进行串扰。这些研究揭示了外泌体在黑素细胞色素沉着中的重要作用，为黑素生成开辟了新途径。
