Partially purified Curcuma longa inhibits alpha‐melanocyte‐stimulating hormone‐stimulated melanogenesis through extracellular signal‐regulated kinase or Akt activation‐mediated signalling in B16F10 cells

Abstract

Bioassay‐guided fractionation of Curcuma longa by solvent partitioning and purification with octadecylsilane open column chromatography yielded a partial purification. The active 80% methanol chromatographic fraction from the ethyl acetate layer [partial purification from C. longa (PPC)] was used to investigate the alpha‐melanocyte‐stimulating hormone (α‐MSH)‐stimulated melanogenesis signal pathway in B16F10 cells. In cells stimulated α‐MSH, PPC inhibited cellular melanin contents, tyrosinase activity and expression of melanogenesis‐related proteins including microphthalmia‐associated transcription factor (MITF), tyrosinase and tyrosinase‐related proteins (TRP). Melanogenesis‐regulating signalling such as mitogen‐activated protein kinase (MEK)/extracellular signal‐regulated kinase (ERK) and phosphatidylinositol 3‐kinase (PI3K)/Akt was activated by PPC in α‐MSH‐stimulated B16F10 cells. The suppressive activity of PPC on α‐MSH‐induced melanogenesis was abrogated by selective inhibition of MEK/ERK (PD98059) and PI3K (LY294002). MEK/ERK or Akt activation by PPC may contribute to reduced melanin synthesis via MITF and its downstream signal pathway including tyrosinase and TRPs in α‐MSH‐induced melanogenesis.

Part of CIRS Nexus · Curated by Lauren Lowenstein, The Biotoxin Lady