Potassium 4-Methoxysalicylate (4MSK) Exerts a Skin Lightening Effect by Acting on Melanocytes and Keratinocytes

• TR Number: 1070
• Authors: Yutaka Shirasugi1 | Takako Shibata1 | Saaya Koike1 | Masao Hara, Kiyotaka Hasegawa, Masato Iino, Aska Sonoki, Yoko Funasaka
• Keywords: MelanoDerm, MEL-300-A, EPI-100-NMM-113 skin lightening, skin brightening, pigmentation, potassium 4-methoxysalicylate, macroscopic lightening, melanin assay, NaOH melanin extraction, Fontana-Masson staining, filaggrin, loricrin, Hoechst 33342
• Materials Tested: potassium 4-methoxysalicylate
• Link to Article: https://pubmed.ncbi.nlm.nih.gov/40071590/

Hyperpigmentation is a common acquired disorder that can be a cosmetic concern for many individuals. To reduce and prevent hyperpigmentation, numerous skin lightening agents have been developed. Potassium 4-methoxysalicylate (4MSK) is a skin lightening agent that was approved as an active skin lightening ingredient of quasi-drugs by the Ministry of Health, Labour and Welfare of Japan in 2003. For over 20 years, 4MSK has been widely used in quasi-drug and cosmetic products. However, the mechanism of action and efficacy of 4MSK on skin pigmentation and skin lightness have not been publicly reported.