Tranexamic Acid Diminishes Laser-Induced Melanogenesis = Tranexamic Acid Diminishes Laser-Induced Melanogenesis

다국어 초록 (Multilingual Abstract)

Background: The treatment of post-inflammatory hyperpigmentation (PIH) remains challenging. Tranexamic acid, a well-known anti-fibrinolytic drug, has recently demonstrated a curative effect towards melasma and ultraviolet- induced PIH in Asian countries. However, the precise mechanism of its inhibitory effect on melanogenesis is not fully understood. Objective: In order to clarify the inhibitory effect of tranexamic acid on PIH, we investigated its effects on mouse melanocytes (i.e., melan-a cells) and human melanocytes. Methods: Melan-a cells and human melanocytes were cultured with fractional CO2 laser-treated keratinocyte- conditioned media. Melanin content and tyrosinase activity were evaluated in cells treated with or without tranexamic acid. Protein levels of tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 were evaluated in melan-a cells. Signaling pathway molecules involved in melanogenesis in melanoma cells were also investigated. Results: Tranexamic acid-treated melanocytes exhibited reduced melanin content and tyrosinase activity. Tranexamic acid also decreased tyrosinase, TRP-1, and TRP-2 protein levels. This inhibitory effect on melanogenesis was considered to be involved in extracellular signal-regulated kinase signaling pathways and subsequently microphthalmia-associated transcription factor degradation. Conclusion: Tranexamic acid may be an attractive candidate for the treatment of PIH. (Ann Dermatol 27(3) 250∼256, 2015)