Effect of Tunisian Aromatic Plant Extracts on Melanogenesis

Abstract

Melanin plays an important role in the prevention of DNA damage and protection of skin tissues from UV irradiation. However, excessive accumulation of melanin can also cause freckle and melanoma. Thus, we focused on the melanogenesis regulation effect of Tunisian aromatic plants. The melanin synthesis system is known as melanogenesis, and tyrosinase is a key enzyme of melanogenesis (Fang and Setaluri, 1999; Kameyama et al., 1995). Currently, many research efforts have focused on the specific mechanism involved in melanogenesis. It has been reported that ERK1/2 phosphorylation is related to the inhibition of melanogenesis (Kim et al., 2006). Murine melanoma B16 cells were treated with the extract of Tunisian aromatic plants, namely, Capparis spinosa, Erica multiflora and Thymelaea hirsuta, and then cell viability and synthesized melanin content were measured. The C. spinosa and E. multiflora extract increased the synthesized melanin content in B16 cells without cytotoxity. The tyrosinase expression was clearly increased in cells treated with the extracts. The T. hirsuta extract significantly decreased the synthesized melanin content in B16 cells without cytotoxicity. ERK1/2 was immediately phosphorylated in cells just after treatment with the extract. The tyrosinase expression was inhibited in cells treated with the extracts.