Alexander KM Leung - Involvement of p38 MAPK Signaling Pathway in The Anti-melanogenic Effect of San-bai-tang, A Chinese Herbal Formula, in B16 Cells

Version 1

      Publication Details (including relevant citation   information):

      Journal   of Ethnopharmacology,  Vol.   132(2), 533-535 (2010)

      Abstract:

      Aim of the study

      San-bai-tang (SBT), a Chinese herbal formula, is traditionally   used as a skin whitener in China. In our previous screening   assays, SBT was identified as an effective tyrosinase inhibitor.   In this study, we aim to investigate the anti-melanogenic effect   and mechanisms of SBT in B16 cells.

      Materials and methods

      Cell viability was examined by the MTT assay. Cellular tyrosinase   activity and melanin content were determined using   spectrophotographic methods. Protein expression was analyzed by   immunoblotting.

      Results

      SBT inhibited tyrosinase activity with an IC50 of   215.6 ± 10.3 μg/ml, and decreased cellular melanin content with   an IC50 of 254.8 ± 14.5 μg/ml at 48 h. MTT assay   demonstrated that 48-h SBT (50–400 μg/ml) treatment did not show   obvious cytotoxicity. Immunoblot analysis showed that SBT (100,   200 or 400 μg/ml) treatment for 48 h down-regulated the   expression levels of phosphorylated-p38, MITF, tyrosinase, TRP-1   and TRP-2 in a dose-dependent manner.

      Conclusions

      SBT inhibited melanogenesis in B16 cells, and suppression of p38   MAPK signaling pathway contributed to the anti-melanogenic effect   of SBT by down-regulating the expression of MITF and melanogenic   enzymes. These novel findings demonstrated the anti-melanogenic   effect and mechanisms of SBT, and provide pharmacological basis   for the traditional use of SBT.

      Address (URL): http://dx.doi.org/10.1016/j.jep.2010.09.007