Towards New Aspects of Melatonin Research in Dermato-Endocrinology

The document discusses the multifaceted role of melatonin in skin biology and dermato-endocrinology, based on research conducted using human cell models such as keratinocytes and fibroblasts. Melatonin has been shown to act as a protective agent against various forms of skin stress, including ultraviolet radiation and chemotherapy-induced cytotoxicity, by functioning as a radical scavenger and modulating cell growth through different types of receptors. It also influences secondary endocrine signaling in the skin. Notably, melatonin levels found in human keratinocytes and hair follicles are significantly higher than in plasma, and its production can be increased by noradrenalin. The study also identified a melatoninergic antioxidative system in the skin, which is enhanced by UV exposure. Additionally, melatonin indirectly protects cells by up-regulating the expression and activity of an intracellular antioxidative enzyme network. Two human organ culture models were used to further investigate the effects of melatonin on human skin and hair under stress conditions such as UV radiation and chemotherapy, revealing that melatonin reduces UV-damaged keratinocytes and has anti-apoptotic effects on hair follicles damaged by chemotherapy.