Abstract

Mentha spicata is a herb with several biological properties. Cytotoxicity of essential oils ofM. spicata on some cancer cells has been reported. In this study the cytotoxicity of aqueous extract of M. spicata on two tumor cell lines (Wehi-164 fibrosarcoma and U937 leukemic monocyte) has been evaluated in vitro. Wehi-164 and U937 cells were separately cultured in RPMI with 10% FBS. Then the cells at logarithmic growth phase were incubated in the presence of different concentrations of aqueous extract of M. spicata (0.1 to 10 mg/ml) at 24, 48 and 72 h periods. The cell proliferation was assessed with trypan blue dye exclusion and MTT assays. Aqueous extract of M. spicata significantly reduced the proliferation of Wehi-164 and U937 cells dose and time-dependently. The LD 50 values of M. spicata extract were 5.97, 4.63 and 4.77 mg/ml for the Wehi-164 cells and 5.6, 5.3 and 4.84 mg/ml for the U937 cells, after 24, 48 and 72 h treatment respectively. Aqueous extract ofM. spicata showed cytotoxic effect in mouse fibrosarcoma Wehi-164 and human monocytic U937 cells. Thus, M. spicata could have potential anti-tumor activity. In vivo studies as well as identification of effective components of M. spicata with anti-cancer activity and their exact mechanism of action could be useful in designing new anti-cancer therapeutic agents.

Key words: Mentha spicata, cytotoxicity, cancer.