Placental extracts induce the expression of antioxidant enzyme genes and suppress melanogenesis in B16 melanoma cells

Abstract

One of the activities of placental extracts (PEs) is skin-whitening effect, but the physiological and genetic mechanism for this effect has not yet been clarified. Here, we focus on PE as a regulator of antioxidant enzyme genes. Porcine PE was prepared, and its activity was investigated in B16 melanoma cells. PE treatment decreased the melanin content of UV-irradiated B16 cells in a dose-dependent manner. PE directly reduced the enzyme activity of tyrosinase in a cell-free assay. In addition, PE treatment increased the gene expression of cytosolic superoxide dismutase (SOD-1), extracellular SOD (SOD-3) and catalase but did not affect the expression of tyrosinase. Moreover, PE protected the B16 cells from H₂O₂-induced cell death. Taken together, our data suggest that PEs could play a role not only as a suppressor of melanin synthesis but also as a regulator of antioxidant genes and might protect the skin against oxidative stress.

Keywords::

• placenta extracts
• melanin synthesis
• superoxide dismutase
• antioxidant enzyme

Acknowledgements

We are grateful to Hiroshi Takahashi, Ph.D. (Snowden Co., Tokyo, Japan) for providing the porcine PEs (Hydrolysed placental extract, Lot TP53/54).

Notes

^1. The present affiliation is College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.