Shiseido Global Innovation Center, Yokohama, Japan.
Graduate Department of Electronics, Tohoku Institute of Technology, Sendai, Japan.
J Photochem Photobiol B. 2019 Sep;198:111562. doi: 10.1016/j.jphotobiol.2019.111562. Epub 2019 Jul 17.
Ultraweak photon emission (UPE) is generally observed in living organisms and often designated as biophoton emission. UPE is detectable from human skin, and its intensity increases by external stress such as ultraviolet (UV) irradiation. Presently, UPE measurement is used to evaluate oxidation status. The fact that the electronically excited species responsible for UPE are formed by reactive oxygen species (ROS)-induced lipid peroxidation and protein and nucleic acid oxidation is well known. The human skin undergoes oxidative stress by UV irradiation, resulting in various skin complications; therefore, it is essential to know the oxidation status of the skin. In this study, we assessed the characteristics of UV-induced UPE in the skin by the imaging and spectroscopy systems. Two-dimensional images obtained by a highly sensitive imaging system using a cooled charge-coupled device (CCD) camera revealed that UPE intensity increases with the amount of UV and is suppressed by antioxidants. Additionally, it is indicated that UPE is generated not only from the epidermis but also from the dermis. The spectra of UPE induced by UVA or UVB showed similar peaks in the visible light region. Furthermore, we confirmed the efficiency of sunscreen by the imaging technique. UPE measurement is a useful method to evaluate UV-induced oxidation in the human skin, and UPE imaging is an effective method to visually evaluate oxidative stress in the human skin.
超弱发光（UPE）通常在生物体中观察到，通常被指定为生物光子发射。UPE 可从人体皮肤中检测到，其强度会因紫外线（UV）照射等外部应激而增加。目前，UPE 测量被用于评估氧化状态。众所周知，负责 UPE 的电子激发物种是由活性氧（ROS）诱导的脂质过氧化以及蛋白质和核酸氧化形成的。人体皮肤受到紫外线照射会产生氧化应激，导致各种皮肤并发症；因此，了解皮肤的氧化状态至关重要。在这项研究中，我们使用成像和光谱系统评估了皮肤中由紫外线诱导的 UPE 的特性。使用冷却电荷耦合器件（CCD）相机的高灵敏度成像系统获得的二维图像表明，UPE 强度随紫外线量的增加而增加，并被抗氧化剂抑制。此外，表明 UPE 不仅从表皮而且从真皮中产生。UVA 或 UVB 诱导的 UPE 的光谱在可见光区域显示出相似的峰。此外，我们通过成像技术证实了防晒霜的功效。UPE 测量是评估人体皮肤中紫外线诱导氧化的有用方法，而 UPE 成像则是有效评估人体皮肤氧化应激的方法。
