Methimazole Is an Inhibitor of Melanin Synthesis in Cultured B16 Melanocytes  Behrooz Kasraee, Ambros Hügin, Christian Tran, Olivier Sorg, Jean-Hilaire Saurat  Journal of Investigative Dermatology  Volume 122, Issue 5, Pages 1338-1341 (May 2004) DOI: 10.1111/j.0022-202X.2004.22509.x Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 Effect of MMI on melanogenesis. MMI was added at various concentrations on B16 melanocytes, and then melanin content and MTT assay were performed (A). For MTT assay, 100 μl of a 5 mg per ml MTT solution was added to each well and the plates were incubated for 3 h at 37°C. The formed MTT formazan crystals were dissolved by adding 500 μL DMSO, and spectrophotometric assay was carried out at 500 nm. (B) Ratio of melanin content (μg) per μmol of MTT formazan produced, for the same number of cells. Journal of Investigative Dermatology 2004 122, 1338-1341DOI: (10.1111/j.0022-202X.2004.22509.x) Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 Effect of hydroquinone on melanogenesis. See Figure 1 legend. The melanin/MTT formazan ratio increases for concentrations higher than 10 μM; this is due to the very low number of cells, as revealed by the MTT assay, but has no biological relevance. Journal of Investigative Dermatology 2004 122, 1338-1341DOI: (10.1111/j.0022-202X.2004.22509.x) Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 3 Effect of arbutin on melanogenesis. See Figure 1 legend. Journal of Investigative Dermatology 2004 122, 1338-1341DOI: (10.1111/j.0022-202X.2004.22509.x) Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 4 Effect of kojic acid on melanogenesis. See Figure 1 legend. Journal of Investigative Dermatology 2004 122, 1338-1341DOI: (10.1111/j.0022-202X.2004.22509.x) Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 5 Cytotoxicity of MMI, hydroquinone, arbutin, and kojic acid on BDVII keratinocytes. The cytotoxicity was assessed by using the MTT assay (see Figure 1 legend). Journal of Investigative Dermatology 2004 122, 1338-1341DOI: (10.1111/j.0022-202X.2004.22509.x) Copyright © 2004 The Society for Investigative Dermatology, Inc Terms and Conditions