ABSTRACT The skin protects our body from various external factors, such as chemical and physical stimuli, microorganisms, and sunlight. Sunlight is a representative environmental factor that considerably influences the physiological activity of our bodies. The molecular mechanisms and detrimental effects of ultraviolet rays (UVR) on skin have been thoroughly investigated. Chronic exposure to UVR generally causes skin damage and eventually induces wrinkle formation and reduced elasticity of the skin. Several studies have shown that infrared rays (IR) also lead to the breakdown of collagen fibers in the skin. However, several reports have demonstrated that the appropriate use of UVR or IR can have beneficial effects on skin-related diseases. Additionally, it has been revealed that visible light of different wavelengths has various biological effects on the skin. Interestingly, several recent studies have reported that photoreceptors are also expressed in the skin, similar to those in the eyes. Based on these data, I discuss the various physiological effects of sunlight on the skin and provide insights on the use of phototherapy, which uses a specific wavelength of sunlight as a non-invasive method, to improve skin-related disorders.

中文翻译：

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太阳辐射对皮肤的各种生物效应及其机制：对光疗的影响

摘要 皮肤保护我们的身体免受各种外部因素的影响，例如化学和物理刺激、微生物和阳光。阳光是一种有代表性的环境因素，对我们身体的生理活动有很大影响。已经彻底研究了紫外线 (UVR) 对皮肤的分子机制和有害影响。长期暴露于 UVR 通常会导致皮肤损伤，并最终导致皱纹形成和皮肤弹性降低。多项研究表明，红外线 (IR) 也会导致皮肤中的胶原纤维分解。然而，一些报告表明，适当使用 UVR 或 IR 可以对皮肤相关疾病产生有益的影响。此外，研究表明，不同波长的可见光对皮肤具有不同的生物效应。有趣的是，最近的几项研究报告称，光感受器也在皮肤中表达，类似于眼睛中的那些。基于这些数据，我讨论了阳光对皮肤的各种生理影响，并提供了关于使用光疗的见解，光疗使用特定波长的阳光作为非侵入性方法来改善皮肤相关疾病。